github.com/rohankumardubey/syslog-redirector-golang@v0.0.0-20140320174030-4859f03d829a/src/cmd/gc/go.y (about)

     1  // Copyright 2009 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  /*
     6   * Go language grammar.
     7   *
     8   * The Go semicolon rules are:
     9   *
    10   *  1. all statements and declarations are terminated by semicolons.
    11   *  2. semicolons can be omitted before a closing ) or }.
    12   *  3. semicolons are inserted by the lexer before a newline
    13   *      following a specific list of tokens.
    14   *
    15   * Rules #1 and #2 are accomplished by writing the lists as
    16   * semicolon-separated lists with an optional trailing semicolon.
    17   * Rule #3 is implemented in yylex.
    18   */
    19  
    20  %{
    21  #include <u.h>
    22  #include <stdio.h>	/* if we don't, bison will, and go.h re-#defines getc */
    23  #include <libc.h>
    24  #include "go.h"
    25  
    26  static void fixlbrace(int);
    27  %}
    28  %union	{
    29  	Node*		node;
    30  	NodeList*		list;
    31  	Type*		type;
    32  	Sym*		sym;
    33  	struct	Val	val;
    34  	int		i;
    35  }
    36  
    37  // |sed 's/.*	//' |9 fmt -l1 |sort |9 fmt -l50 | sed 's/^/%xxx		/'
    38  
    39  %token	<val>	LLITERAL
    40  %token	<i>	LASOP LCOLAS
    41  %token	<sym>	LBREAK LCASE LCHAN LCONST LCONTINUE LDDD
    42  %token	<sym>	LDEFAULT LDEFER LELSE LFALL LFOR LFUNC LGO LGOTO
    43  %token	<sym>	LIF LIMPORT LINTERFACE LMAP LNAME
    44  %token	<sym>	LPACKAGE LRANGE LRETURN LSELECT LSTRUCT LSWITCH
    45  %token	<sym>	LTYPE LVAR
    46  
    47  %token		LANDAND LANDNOT LBODY LCOMM LDEC LEQ LGE LGT
    48  %token		LIGNORE LINC LLE LLSH LLT LNE LOROR LRSH
    49  
    50  %type	<i>	lbrace import_here
    51  %type	<sym>	sym packname
    52  %type	<val>	oliteral
    53  
    54  %type	<node>	stmt ntype
    55  %type	<node>	arg_type
    56  %type	<node>	case caseblock
    57  %type	<node>	compound_stmt dotname embed expr complitexpr bare_complitexpr
    58  %type	<node>	expr_or_type
    59  %type	<node>	fndcl hidden_fndcl fnliteral
    60  %type	<node>	for_body for_header for_stmt if_header if_stmt non_dcl_stmt
    61  %type	<node>	interfacedcl keyval labelname name
    62  %type	<node>	name_or_type non_expr_type
    63  %type	<node>	new_name dcl_name oexpr typedclname
    64  %type	<node>	onew_name
    65  %type	<node>	osimple_stmt pexpr pexpr_no_paren
    66  %type	<node>	pseudocall range_stmt select_stmt
    67  %type	<node>	simple_stmt
    68  %type	<node>	switch_stmt uexpr
    69  %type	<node>	xfndcl typedcl start_complit
    70  
    71  %type	<list>	xdcl fnbody fnres loop_body dcl_name_list
    72  %type	<list>	new_name_list expr_list keyval_list braced_keyval_list expr_or_type_list xdcl_list
    73  %type	<list>	oexpr_list caseblock_list elseif elseif_list else stmt_list oarg_type_list_ocomma arg_type_list
    74  %type	<list>	interfacedcl_list vardcl vardcl_list structdcl structdcl_list
    75  %type	<list>	common_dcl constdcl constdcl1 constdcl_list typedcl_list
    76  
    77  %type	<node>	convtype comptype dotdotdot
    78  %type	<node>	indcl interfacetype structtype ptrtype
    79  %type	<node>	recvchantype non_recvchantype othertype fnret_type fntype
    80  
    81  %type	<sym>	hidden_importsym hidden_pkg_importsym
    82  
    83  %type	<node>	hidden_constant hidden_literal hidden_funarg
    84  %type	<node>	hidden_interfacedcl hidden_structdcl
    85  
    86  %type	<list>	hidden_funres
    87  %type	<list>	ohidden_funres
    88  %type	<list>	hidden_funarg_list ohidden_funarg_list
    89  %type	<list>	hidden_interfacedcl_list ohidden_interfacedcl_list
    90  %type	<list>	hidden_structdcl_list ohidden_structdcl_list
    91  
    92  %type	<type>	hidden_type hidden_type_misc hidden_pkgtype
    93  %type	<type>	hidden_type_func
    94  %type	<type>	hidden_type_recv_chan hidden_type_non_recv_chan
    95  
    96  %left		LCOMM	/* outside the usual hierarchy; here for good error messages */
    97  
    98  %left		LOROR
    99  %left		LANDAND
   100  %left		LEQ LNE LLE LGE LLT LGT
   101  %left		'+' '-' '|' '^'
   102  %left		'*' '/' '%' '&' LLSH LRSH LANDNOT
   103  
   104  /*
   105   * manual override of shift/reduce conflicts.
   106   * the general form is that we assign a precedence
   107   * to the token being shifted and then introduce
   108   * NotToken with lower precedence or PreferToToken with higher
   109   * and annotate the reducing rule accordingly.
   110   */
   111  %left		NotPackage
   112  %left		LPACKAGE
   113  
   114  %left		NotParen
   115  %left		'('
   116  
   117  %left		')'
   118  %left		PreferToRightParen
   119  
   120  %error-verbose
   121  
   122  %%
   123  file:
   124  	loadsys
   125  	package
   126  	imports
   127  	xdcl_list
   128  	{
   129  		xtop = concat(xtop, $4);
   130  	}
   131  
   132  package:
   133  	%prec NotPackage
   134  	{
   135  		prevlineno = lineno;
   136  		yyerror("package statement must be first");
   137  		errorexit();
   138  	}
   139  |	LPACKAGE sym ';'
   140  	{
   141  		mkpackage($2->name);
   142  	}
   143  
   144  /*
   145   * this loads the definitions for the low-level runtime functions,
   146   * so that the compiler can generate calls to them,
   147   * but does not make the name "runtime" visible as a package.
   148   */
   149  loadsys:
   150  	{
   151  		importpkg = runtimepkg;
   152  
   153  		if(debug['A'])
   154  			cannedimports("runtime.builtin", "package runtime\n\n$$\n\n");
   155  		else
   156  			cannedimports("runtime.builtin", runtimeimport);
   157  		curio.importsafe = 1;
   158  	}
   159  	import_package
   160  	import_there
   161  	{
   162  		importpkg = nil;
   163  	}
   164  
   165  imports:
   166  |	imports import ';'
   167  
   168  import:
   169  	LIMPORT import_stmt
   170  |	LIMPORT '(' import_stmt_list osemi ')'
   171  |	LIMPORT '(' ')'
   172  
   173  import_stmt:
   174  	import_here import_package import_there
   175  	{
   176  		Pkg *ipkg;
   177  		Sym *my;
   178  		Node *pack;
   179  		
   180  		ipkg = importpkg;
   181  		my = importmyname;
   182  		importpkg = nil;
   183  		importmyname = S;
   184  
   185  		if(my == nil)
   186  			my = lookup(ipkg->name);
   187  
   188  		pack = nod(OPACK, N, N);
   189  		pack->sym = my;
   190  		pack->pkg = ipkg;
   191  		pack->lineno = $1;
   192  
   193  		if(my->name[0] == '.') {
   194  			importdot(ipkg, pack);
   195  			break;
   196  		}
   197  		if(strcmp(my->name, "init") == 0) {
   198  			yyerror("cannot import package as init - init must be a func");
   199  			break;
   200  		}
   201  		if(my->name[0] == '_' && my->name[1] == '\0')
   202  			break;
   203  		if(my->def) {
   204  			lineno = $1;
   205  			redeclare(my, "as imported package name");
   206  		}
   207  		my->def = pack;
   208  		my->lastlineno = $1;
   209  		my->block = 1;	// at top level
   210  	}
   211  |	import_here import_there
   212  	{
   213  		// When an invalid import path is passed to importfile,
   214  		// it calls yyerror and then sets up a fake import with
   215  		// no package statement. This allows us to test more
   216  		// than one invalid import statement in a single file.
   217  		if(nerrors == 0)
   218  			fatal("phase error in import");
   219  	}
   220  
   221  import_stmt_list:
   222  	import_stmt
   223  |	import_stmt_list ';' import_stmt
   224  
   225  import_here:
   226  	LLITERAL
   227  	{
   228  		// import with original name
   229  		$$ = parserline();
   230  		importmyname = S;
   231  		importfile(&$1, $$);
   232  	}
   233  |	sym LLITERAL
   234  	{
   235  		// import with given name
   236  		$$ = parserline();
   237  		importmyname = $1;
   238  		importfile(&$2, $$);
   239  	}
   240  |	'.' LLITERAL
   241  	{
   242  		// import into my name space
   243  		$$ = parserline();
   244  		importmyname = lookup(".");
   245  		importfile(&$2, $$);
   246  	}
   247  
   248  import_package:
   249  	LPACKAGE LNAME import_safety ';'
   250  	{
   251  		if(importpkg->name == nil) {
   252  			importpkg->name = $2->name;
   253  			pkglookup($2->name, nil)->npkg++;
   254  		} else if(strcmp(importpkg->name, $2->name) != 0)
   255  			yyerror("conflicting names %s and %s for package \"%Z\"", importpkg->name, $2->name, importpkg->path);
   256  		importpkg->direct = 1;
   257  		importpkg->safe = curio.importsafe;
   258  
   259  		if(safemode && !curio.importsafe)
   260  			yyerror("cannot import unsafe package \"%Z\"", importpkg->path);
   261  	}
   262  
   263  import_safety:
   264  |	LNAME
   265  	{
   266  		if(strcmp($1->name, "safe") == 0)
   267  			curio.importsafe = 1;
   268  	}
   269  
   270  import_there:
   271  	{
   272  		defercheckwidth();
   273  	}
   274  	hidden_import_list '$' '$'
   275  	{
   276  		resumecheckwidth();
   277  		unimportfile();
   278  	}
   279  
   280  /*
   281   * declarations
   282   */
   283  xdcl:
   284  	{
   285  		yyerror("empty top-level declaration");
   286  		$$ = nil;
   287  	}
   288  |	common_dcl
   289  |	xfndcl
   290  	{
   291  		$$ = list1($1);
   292  	}
   293  |	non_dcl_stmt
   294  	{
   295  		yyerror("non-declaration statement outside function body");
   296  		$$ = nil;
   297  	}
   298  |	error
   299  	{
   300  		$$ = nil;
   301  	}
   302  
   303  common_dcl:
   304  	LVAR vardcl
   305  	{
   306  		$$ = $2;
   307  	}
   308  |	LVAR '(' vardcl_list osemi ')'
   309  	{
   310  		$$ = $3;
   311  	}
   312  |	LVAR '(' ')'
   313  	{
   314  		$$ = nil;
   315  	}
   316  |	lconst constdcl
   317  	{
   318  		$$ = $2;
   319  		iota = -100000;
   320  		lastconst = nil;
   321  	}
   322  |	lconst '(' constdcl osemi ')'
   323  	{
   324  		$$ = $3;
   325  		iota = -100000;
   326  		lastconst = nil;
   327  	}
   328  |	lconst '(' constdcl ';' constdcl_list osemi ')'
   329  	{
   330  		$$ = concat($3, $5);
   331  		iota = -100000;
   332  		lastconst = nil;
   333  	}
   334  |	lconst '(' ')'
   335  	{
   336  		$$ = nil;
   337  		iota = -100000;
   338  	}
   339  |	LTYPE typedcl
   340  	{
   341  		$$ = list1($2);
   342  	}
   343  |	LTYPE '(' typedcl_list osemi ')'
   344  	{
   345  		$$ = $3;
   346  	}
   347  |	LTYPE '(' ')'
   348  	{
   349  		$$ = nil;
   350  	}
   351  
   352  lconst:
   353  	LCONST
   354  	{
   355  		iota = 0;
   356  	}
   357  
   358  vardcl:
   359  	dcl_name_list ntype
   360  	{
   361  		$$ = variter($1, $2, nil);
   362  	}
   363  |	dcl_name_list ntype '=' expr_list
   364  	{
   365  		$$ = variter($1, $2, $4);
   366  	}
   367  |	dcl_name_list '=' expr_list
   368  	{
   369  		$$ = variter($1, nil, $3);
   370  	}
   371  
   372  constdcl:
   373  	dcl_name_list ntype '=' expr_list
   374  	{
   375  		$$ = constiter($1, $2, $4);
   376  	}
   377  |	dcl_name_list '=' expr_list
   378  	{
   379  		$$ = constiter($1, N, $3);
   380  	}
   381  
   382  constdcl1:
   383  	constdcl
   384  |	dcl_name_list ntype
   385  	{
   386  		$$ = constiter($1, $2, nil);
   387  	}
   388  |	dcl_name_list
   389  	{
   390  		$$ = constiter($1, N, nil);
   391  	}
   392  
   393  typedclname:
   394  	sym
   395  	{
   396  		// different from dclname because the name
   397  		// becomes visible right here, not at the end
   398  		// of the declaration.
   399  		$$ = typedcl0($1);
   400  	}
   401  
   402  typedcl:
   403  	typedclname ntype
   404  	{
   405  		$$ = typedcl1($1, $2, 1);
   406  	}
   407  
   408  simple_stmt:
   409  	expr
   410  	{
   411  		$$ = $1;
   412  
   413  		// These nodes do not carry line numbers.
   414  		// Since a bare name used as an expression is an error,
   415  		// introduce a wrapper node to give the correct line.
   416  		switch($$->op) {
   417  		case ONAME:
   418  		case ONONAME:
   419  		case OTYPE:
   420  		case OPACK:
   421  		case OLITERAL:
   422  			$$ = nod(OPAREN, $$, N);
   423  			$$->implicit = 1;
   424  			break;
   425  		}
   426  	}
   427  |	expr LASOP expr
   428  	{
   429  		$$ = nod(OASOP, $1, $3);
   430  		$$->etype = $2;			// rathole to pass opcode
   431  	}
   432  |	expr_list '=' expr_list
   433  	{
   434  		if($1->next == nil && $3->next == nil) {
   435  			// simple
   436  			$$ = nod(OAS, $1->n, $3->n);
   437  			break;
   438  		}
   439  		// multiple
   440  		$$ = nod(OAS2, N, N);
   441  		$$->list = $1;
   442  		$$->rlist = $3;
   443  	}
   444  |	expr_list LCOLAS expr_list
   445  	{
   446  		if($3->n->op == OTYPESW) {
   447  			$$ = nod(OTYPESW, N, $3->n->right);
   448  			if($3->next != nil)
   449  				yyerror("expr.(type) must be alone in list");
   450  			if($1->next != nil)
   451  				yyerror("argument count mismatch: %d = %d", count($1), 1);
   452  			else if(($1->n->op != ONAME && $1->n->op != OTYPE && $1->n->op != ONONAME) || isblank($1->n))
   453  				yyerror("invalid variable name %N in type switch", $1->n);
   454  			else
   455  				$$->left = dclname($1->n->sym);  // it's a colas, so must not re-use an oldname.
   456  			break;
   457  		}
   458  		$$ = colas($1, $3, $2);
   459  	}
   460  |	expr LINC
   461  	{
   462  		$$ = nod(OASOP, $1, nodintconst(1));
   463  		$$->etype = OADD;
   464  	}
   465  |	expr LDEC
   466  	{
   467  		$$ = nod(OASOP, $1, nodintconst(1));
   468  		$$->etype = OSUB;
   469  	}
   470  
   471  case:
   472  	LCASE expr_or_type_list ':'
   473  	{
   474  		Node *n, *nn;
   475  
   476  		// will be converted to OCASE
   477  		// right will point to next case
   478  		// done in casebody()
   479  		markdcl();
   480  		$$ = nod(OXCASE, N, N);
   481  		$$->list = $2;
   482  		if(typesw != N && typesw->right != N && (n=typesw->right->left) != N) {
   483  			// type switch - declare variable
   484  			nn = newname(n->sym);
   485  			declare(nn, dclcontext);
   486  			$$->nname = nn;
   487  
   488  			// keep track of the instances for reporting unused
   489  			nn->defn = typesw->right;
   490  		}
   491  	}
   492  |	LCASE expr_or_type_list '=' expr ':'
   493  	{
   494  		Node *n;
   495  
   496  		// will be converted to OCASE
   497  		// right will point to next case
   498  		// done in casebody()
   499  		markdcl();
   500  		$$ = nod(OXCASE, N, N);
   501  		if($2->next == nil)
   502  			n = nod(OAS, $2->n, $4);
   503  		else {
   504  			n = nod(OAS2, N, N);
   505  			n->list = $2;
   506  			n->rlist = list1($4);
   507  		}
   508  		$$->list = list1(n);
   509  	}
   510  |	LCASE expr_or_type_list LCOLAS expr ':'
   511  	{
   512  		// will be converted to OCASE
   513  		// right will point to next case
   514  		// done in casebody()
   515  		markdcl();
   516  		$$ = nod(OXCASE, N, N);
   517  		$$->list = list1(colas($2, list1($4), $3));
   518  	}
   519  |	LDEFAULT ':'
   520  	{
   521  		Node *n, *nn;
   522  
   523  		markdcl();
   524  		$$ = nod(OXCASE, N, N);
   525  		if(typesw != N && typesw->right != N && (n=typesw->right->left) != N) {
   526  			// type switch - declare variable
   527  			nn = newname(n->sym);
   528  			declare(nn, dclcontext);
   529  			$$->nname = nn;
   530  
   531  			// keep track of the instances for reporting unused
   532  			nn->defn = typesw->right;
   533  		}
   534  	}
   535  
   536  compound_stmt:
   537  	'{'
   538  	{
   539  		markdcl();
   540  	}
   541  	stmt_list '}'
   542  	{
   543  		if($3 == nil)
   544  			$$ = nod(OEMPTY, N, N);
   545  		else
   546  			$$ = liststmt($3);
   547  		popdcl();
   548  	}
   549  
   550  caseblock:
   551  	case
   552  	{
   553  		// If the last token read by the lexer was consumed
   554  		// as part of the case, clear it (parser has cleared yychar).
   555  		// If the last token read by the lexer was the lookahead
   556  		// leave it alone (parser has it cached in yychar).
   557  		// This is so that the stmt_list action doesn't look at
   558  		// the case tokens if the stmt_list is empty.
   559  		yylast = yychar;
   560  	}
   561  	stmt_list
   562  	{
   563  		int last;
   564  
   565  		// This is the only place in the language where a statement
   566  		// list is not allowed to drop the final semicolon, because
   567  		// it's the only place where a statement list is not followed 
   568  		// by a closing brace.  Handle the error for pedantry.
   569  
   570  		// Find the final token of the statement list.
   571  		// yylast is lookahead; yyprev is last of stmt_list
   572  		last = yyprev;
   573  
   574  		if(last > 0 && last != ';' && yychar != '}')
   575  			yyerror("missing statement after label");
   576  		$$ = $1;
   577  		$$->nbody = $3;
   578  		popdcl();
   579  	}
   580  
   581  caseblock_list:
   582  	{
   583  		$$ = nil;
   584  	}
   585  |	caseblock_list caseblock
   586  	{
   587  		$$ = list($1, $2);
   588  	}
   589  
   590  loop_body:
   591  	LBODY
   592  	{
   593  		markdcl();
   594  	}
   595  	stmt_list '}'
   596  	{
   597  		$$ = $3;
   598  		popdcl();
   599  	}
   600  
   601  range_stmt:
   602  	expr_list '=' LRANGE expr
   603  	{
   604  		$$ = nod(ORANGE, N, $4);
   605  		$$->list = $1;
   606  		$$->etype = 0;	// := flag
   607  	}
   608  |	expr_list LCOLAS LRANGE expr
   609  	{
   610  		$$ = nod(ORANGE, N, $4);
   611  		$$->list = $1;
   612  		$$->colas = 1;
   613  		colasdefn($1, $$);
   614  	}
   615  
   616  for_header:
   617  	osimple_stmt ';' osimple_stmt ';' osimple_stmt
   618  	{
   619  		// init ; test ; incr
   620  		if($5 != N && $5->colas != 0)
   621  			yyerror("cannot declare in the for-increment");
   622  		$$ = nod(OFOR, N, N);
   623  		if($1 != N)
   624  			$$->ninit = list1($1);
   625  		$$->ntest = $3;
   626  		$$->nincr = $5;
   627  	}
   628  |	osimple_stmt
   629  	{
   630  		// normal test
   631  		$$ = nod(OFOR, N, N);
   632  		$$->ntest = $1;
   633  	}
   634  |	range_stmt
   635  
   636  for_body:
   637  	for_header loop_body
   638  	{
   639  		$$ = $1;
   640  		$$->nbody = concat($$->nbody, $2);
   641  	}
   642  
   643  for_stmt:
   644  	LFOR
   645  	{
   646  		markdcl();
   647  	}
   648  	for_body
   649  	{
   650  		$$ = $3;
   651  		popdcl();
   652  	}
   653  
   654  if_header:
   655  	osimple_stmt
   656  	{
   657  		// test
   658  		$$ = nod(OIF, N, N);
   659  		$$->ntest = $1;
   660  	}
   661  |	osimple_stmt ';' osimple_stmt
   662  	{
   663  		// init ; test
   664  		$$ = nod(OIF, N, N);
   665  		if($1 != N)
   666  			$$->ninit = list1($1);
   667  		$$->ntest = $3;
   668  	}
   669  
   670  /* IF cond body (ELSE IF cond body)* (ELSE block)? */
   671  if_stmt:
   672  	LIF
   673  	{
   674  		markdcl();
   675  	}
   676  	if_header
   677  	{
   678  		if($3->ntest == N)
   679  			yyerror("missing condition in if statement");
   680  	}
   681  	loop_body
   682  	{
   683  		$3->nbody = $5;
   684  	}
   685  	elseif_list else
   686  	{
   687  		Node *n;
   688  		NodeList *nn;
   689  
   690  		$$ = $3;
   691  		n = $3;
   692  		popdcl();
   693  		for(nn = concat($7, $8); nn; nn = nn->next) {
   694  			if(nn->n->op == OIF)
   695  				popdcl();
   696  			n->nelse = list1(nn->n);
   697  			n = nn->n;
   698  		}
   699  	}
   700  
   701  elseif:
   702  	LELSE LIF 
   703  	{
   704  		markdcl();
   705  	}
   706  	if_header loop_body
   707  	{
   708  		if($4->ntest == N)
   709  			yyerror("missing condition in if statement");
   710  		$4->nbody = $5;
   711  		$$ = list1($4);
   712  	}
   713  
   714  elseif_list:
   715  	{
   716  		$$ = nil;
   717  	}
   718  |	elseif_list elseif
   719  	{
   720  		$$ = concat($1, $2);
   721  	}
   722  
   723  else:
   724  	{
   725  		$$ = nil;
   726  	}
   727  |	LELSE compound_stmt
   728  	{
   729  		NodeList *node;
   730  		
   731  		node = mal(sizeof *node);
   732  		node->n = $2;
   733  		node->end = node;
   734  		$$ = node;
   735  	}
   736  
   737  switch_stmt:
   738  	LSWITCH
   739  	{
   740  		markdcl();
   741  	}
   742  	if_header
   743  	{
   744  		Node *n;
   745  		n = $3->ntest;
   746  		if(n != N && n->op != OTYPESW)
   747  			n = N;
   748  		typesw = nod(OXXX, typesw, n);
   749  	}
   750  	LBODY caseblock_list '}'
   751  	{
   752  		$$ = $3;
   753  		$$->op = OSWITCH;
   754  		$$->list = $6;
   755  		typesw = typesw->left;
   756  		popdcl();
   757  	}
   758  
   759  select_stmt:
   760  	LSELECT
   761  	{
   762  		typesw = nod(OXXX, typesw, N);
   763  	}
   764  	LBODY caseblock_list '}'
   765  	{
   766  		$$ = nod(OSELECT, N, N);
   767  		$$->lineno = typesw->lineno;
   768  		$$->list = $4;
   769  		typesw = typesw->left;
   770  	}
   771  
   772  /*
   773   * expressions
   774   */
   775  expr:
   776  	uexpr
   777  |	expr LOROR expr
   778  	{
   779  		$$ = nod(OOROR, $1, $3);
   780  	}
   781  |	expr LANDAND expr
   782  	{
   783  		$$ = nod(OANDAND, $1, $3);
   784  	}
   785  |	expr LEQ expr
   786  	{
   787  		$$ = nod(OEQ, $1, $3);
   788  	}
   789  |	expr LNE expr
   790  	{
   791  		$$ = nod(ONE, $1, $3);
   792  	}
   793  |	expr LLT expr
   794  	{
   795  		$$ = nod(OLT, $1, $3);
   796  	}
   797  |	expr LLE expr
   798  	{
   799  		$$ = nod(OLE, $1, $3);
   800  	}
   801  |	expr LGE expr
   802  	{
   803  		$$ = nod(OGE, $1, $3);
   804  	}
   805  |	expr LGT expr
   806  	{
   807  		$$ = nod(OGT, $1, $3);
   808  	}
   809  |	expr '+' expr
   810  	{
   811  		$$ = nod(OADD, $1, $3);
   812  	}
   813  |	expr '-' expr
   814  	{
   815  		$$ = nod(OSUB, $1, $3);
   816  	}
   817  |	expr '|' expr
   818  	{
   819  		$$ = nod(OOR, $1, $3);
   820  	}
   821  |	expr '^' expr
   822  	{
   823  		$$ = nod(OXOR, $1, $3);
   824  	}
   825  |	expr '*' expr
   826  	{
   827  		$$ = nod(OMUL, $1, $3);
   828  	}
   829  |	expr '/' expr
   830  	{
   831  		$$ = nod(ODIV, $1, $3);
   832  	}
   833  |	expr '%' expr
   834  	{
   835  		$$ = nod(OMOD, $1, $3);
   836  	}
   837  |	expr '&' expr
   838  	{
   839  		$$ = nod(OAND, $1, $3);
   840  	}
   841  |	expr LANDNOT expr
   842  	{
   843  		$$ = nod(OANDNOT, $1, $3);
   844  	}
   845  |	expr LLSH expr
   846  	{
   847  		$$ = nod(OLSH, $1, $3);
   848  	}
   849  |	expr LRSH expr
   850  	{
   851  		$$ = nod(ORSH, $1, $3);
   852  	}
   853  	/* not an expression anymore, but left in so we can give a good error */
   854  |	expr LCOMM expr
   855  	{
   856  		$$ = nod(OSEND, $1, $3);
   857  	}
   858  
   859  uexpr:
   860  	pexpr
   861  |	'*' uexpr
   862  	{
   863  		$$ = nod(OIND, $2, N);
   864  	}
   865  |	'&' uexpr
   866  	{
   867  		if($2->op == OCOMPLIT) {
   868  			// Special case for &T{...}: turn into (*T){...}.
   869  			$$ = $2;
   870  			$$->right = nod(OIND, $$->right, N);
   871  			$$->right->implicit = 1;
   872  		} else {
   873  			$$ = nod(OADDR, $2, N);
   874  		}
   875  	}
   876  |	'+' uexpr
   877  	{
   878  		$$ = nod(OPLUS, $2, N);
   879  	}
   880  |	'-' uexpr
   881  	{
   882  		$$ = nod(OMINUS, $2, N);
   883  	}
   884  |	'!' uexpr
   885  	{
   886  		$$ = nod(ONOT, $2, N);
   887  	}
   888  |	'~' uexpr
   889  	{
   890  		yyerror("the bitwise complement operator is ^");
   891  		$$ = nod(OCOM, $2, N);
   892  	}
   893  |	'^' uexpr
   894  	{
   895  		$$ = nod(OCOM, $2, N);
   896  	}
   897  |	LCOMM uexpr
   898  	{
   899  		$$ = nod(ORECV, $2, N);
   900  	}
   901  
   902  /*
   903   * call-like statements that
   904   * can be preceded by 'defer' and 'go'
   905   */
   906  pseudocall:
   907  	pexpr '(' ')'
   908  	{
   909  		$$ = nod(OCALL, $1, N);
   910  	}
   911  |	pexpr '(' expr_or_type_list ocomma ')'
   912  	{
   913  		$$ = nod(OCALL, $1, N);
   914  		$$->list = $3;
   915  	}
   916  |	pexpr '(' expr_or_type_list LDDD ocomma ')'
   917  	{
   918  		$$ = nod(OCALL, $1, N);
   919  		$$->list = $3;
   920  		$$->isddd = 1;
   921  	}
   922  
   923  pexpr_no_paren:
   924  	LLITERAL
   925  	{
   926  		$$ = nodlit($1);
   927  	}
   928  |	name
   929  |	pexpr '.' sym
   930  	{
   931  		if($1->op == OPACK) {
   932  			Sym *s;
   933  			s = restrictlookup($3->name, $1->pkg);
   934  			$1->used = 1;
   935  			$$ = oldname(s);
   936  			break;
   937  		}
   938  		$$ = nod(OXDOT, $1, newname($3));
   939  	}
   940  |	pexpr '.' '(' expr_or_type ')'
   941  	{
   942  		$$ = nod(ODOTTYPE, $1, $4);
   943  	}
   944  |	pexpr '.' '(' LTYPE ')'
   945  	{
   946  		$$ = nod(OTYPESW, N, $1);
   947  	}
   948  |	pexpr '[' expr ']'
   949  	{
   950  		$$ = nod(OINDEX, $1, $3);
   951  	}
   952  |	pexpr '[' oexpr ':' oexpr ']'
   953  	{
   954  		$$ = nod(OSLICE, $1, nod(OKEY, $3, $5));
   955  	}
   956  |	pexpr '[' oexpr ':' oexpr ':' oexpr ']'
   957  	{
   958  		if($5 == N)
   959  			yyerror("middle index required in 3-index slice");
   960  		if($7 == N)
   961  			yyerror("final index required in 3-index slice");
   962  		$$ = nod(OSLICE3, $1, nod(OKEY, $3, nod(OKEY, $5, $7)));
   963  	}
   964  |	pseudocall
   965  |	convtype '(' expr ocomma ')'
   966  	{
   967  		// conversion
   968  		$$ = nod(OCALL, $1, N);
   969  		$$->list = list1($3);
   970  	}
   971  |	comptype lbrace start_complit braced_keyval_list '}'
   972  	{
   973  		$$ = $3;
   974  		$$->right = $1;
   975  		$$->list = $4;
   976  		fixlbrace($2);
   977  	}
   978  |	pexpr_no_paren '{' start_complit braced_keyval_list '}'
   979  	{
   980  		$$ = $3;
   981  		$$->right = $1;
   982  		$$->list = $4;
   983  	}
   984  |	'(' expr_or_type ')' '{' start_complit braced_keyval_list '}'
   985  	{
   986  		yyerror("cannot parenthesize type in composite literal");
   987  		$$ = $5;
   988  		$$->right = $2;
   989  		$$->list = $6;
   990  	}
   991  |	fnliteral
   992  
   993  start_complit:
   994  	{
   995  		// composite expression.
   996  		// make node early so we get the right line number.
   997  		$$ = nod(OCOMPLIT, N, N);
   998  	}
   999  
  1000  keyval:
  1001  	expr ':' complitexpr
  1002  	{
  1003  		$$ = nod(OKEY, $1, $3);
  1004  	}
  1005  
  1006  bare_complitexpr:
  1007  	expr
  1008  	{
  1009  		// These nodes do not carry line numbers.
  1010  		// Since a composite literal commonly spans several lines,
  1011  		// the line number on errors may be misleading.
  1012  		// Introduce a wrapper node to give the correct line.
  1013  		$$ = $1;
  1014  		switch($$->op) {
  1015  		case ONAME:
  1016  		case ONONAME:
  1017  		case OTYPE:
  1018  		case OPACK:
  1019  		case OLITERAL:
  1020  			$$ = nod(OPAREN, $$, N);
  1021  			$$->implicit = 1;
  1022  		}
  1023  	}
  1024  |	'{' start_complit braced_keyval_list '}'
  1025  	{
  1026  		$$ = $2;
  1027  		$$->list = $3;
  1028  	}
  1029  
  1030  complitexpr:
  1031  	expr
  1032  |	'{' start_complit braced_keyval_list '}'
  1033  	{
  1034  		$$ = $2;
  1035  		$$->list = $3;
  1036  	}
  1037  
  1038  pexpr:
  1039  	pexpr_no_paren
  1040  |	'(' expr_or_type ')'
  1041  	{
  1042  		$$ = $2;
  1043  		
  1044  		// Need to know on lhs of := whether there are ( ).
  1045  		// Don't bother with the OPAREN in other cases:
  1046  		// it's just a waste of memory and time.
  1047  		switch($$->op) {
  1048  		case ONAME:
  1049  		case ONONAME:
  1050  		case OPACK:
  1051  		case OTYPE:
  1052  		case OLITERAL:
  1053  		case OTYPESW:
  1054  			$$ = nod(OPAREN, $$, N);
  1055  		}
  1056  	}
  1057  
  1058  expr_or_type:
  1059  	expr
  1060  |	non_expr_type	%prec PreferToRightParen
  1061  
  1062  name_or_type:
  1063  	ntype
  1064  
  1065  lbrace:
  1066  	LBODY
  1067  	{
  1068  		$$ = LBODY;
  1069  	}
  1070  |	'{'
  1071  	{
  1072  		$$ = '{';
  1073  	}
  1074  
  1075  /*
  1076   * names and types
  1077   *	newname is used before declared
  1078   *	oldname is used after declared
  1079   */
  1080  new_name:
  1081  	sym
  1082  	{
  1083  		if($1 == S)
  1084  			$$ = N;
  1085  		else
  1086  			$$ = newname($1);
  1087  	}
  1088  
  1089  dcl_name:
  1090  	sym
  1091  	{
  1092  		$$ = dclname($1);
  1093  	}
  1094  
  1095  onew_name:
  1096  	{
  1097  		$$ = N;
  1098  	}
  1099  |	new_name
  1100  
  1101  sym:
  1102  	LNAME
  1103  	{
  1104  		$$ = $1;
  1105  		// during imports, unqualified non-exported identifiers are from builtinpkg
  1106  		if(importpkg != nil && !exportname($1->name))
  1107  			$$ = pkglookup($1->name, builtinpkg);
  1108  	}
  1109  |	hidden_importsym
  1110  |	'?'
  1111  	{
  1112  		$$ = S;
  1113  	}
  1114  
  1115  hidden_importsym:
  1116  	'@' LLITERAL '.' LNAME
  1117  	{
  1118  		Pkg *p;
  1119  
  1120  		if($2.u.sval->len == 0)
  1121  			p = importpkg;
  1122  		else {
  1123  			if(isbadimport($2.u.sval))
  1124  				errorexit();
  1125  			p = mkpkg($2.u.sval);
  1126  		}
  1127  		$$ = pkglookup($4->name, p);
  1128  	}
  1129  |	'@' LLITERAL '.' '?'
  1130  	{
  1131  		Pkg *p;
  1132  
  1133  		if($2.u.sval->len == 0)
  1134  			p = importpkg;
  1135  		else {
  1136  			if(isbadimport($2.u.sval))
  1137  				errorexit();
  1138  			p = mkpkg($2.u.sval);
  1139  		}
  1140  		$$ = pkglookup("?", p);
  1141  	}
  1142  
  1143  name:
  1144  	sym	%prec NotParen
  1145  	{
  1146  		$$ = oldname($1);
  1147  		if($$->pack != N)
  1148  			$$->pack->used = 1;
  1149  	}
  1150  
  1151  labelname:
  1152  	new_name
  1153  
  1154  /*
  1155   * to avoid parsing conflicts, type is split into
  1156   *	channel types
  1157   *	function types
  1158   *	parenthesized types
  1159   *	any other type
  1160   * the type system makes additional restrictions,
  1161   * but those are not implemented in the grammar.
  1162   */
  1163  dotdotdot:
  1164  	LDDD
  1165  	{
  1166  		yyerror("final argument in variadic function missing type");
  1167  		$$ = nod(ODDD, typenod(typ(TINTER)), N);
  1168  	}
  1169  |	LDDD ntype
  1170  	{
  1171  		$$ = nod(ODDD, $2, N);
  1172  	}
  1173  
  1174  ntype:
  1175  	recvchantype
  1176  |	fntype
  1177  |	othertype
  1178  |	ptrtype
  1179  |	dotname
  1180  |	'(' ntype ')'
  1181  	{
  1182  		$$ = nod(OTPAREN, $2, N);
  1183  	}
  1184  
  1185  non_expr_type:
  1186  	recvchantype
  1187  |	fntype
  1188  |	othertype
  1189  |	'*' non_expr_type
  1190  	{
  1191  		$$ = nod(OIND, $2, N);
  1192  	}
  1193  
  1194  non_recvchantype:
  1195  	fntype
  1196  |	othertype
  1197  |	ptrtype
  1198  |	dotname
  1199  |	'(' ntype ')'
  1200  	{
  1201  		$$ = nod(OTPAREN, $2, N);
  1202  	}
  1203  
  1204  convtype:
  1205  	fntype
  1206  |	othertype
  1207  
  1208  comptype:
  1209  	othertype
  1210  
  1211  fnret_type:
  1212  	recvchantype
  1213  |	fntype
  1214  |	othertype
  1215  |	ptrtype
  1216  |	dotname
  1217  
  1218  dotname:
  1219  	name
  1220  |	name '.' sym
  1221  	{
  1222  		if($1->op == OPACK) {
  1223  			Sym *s;
  1224  			s = restrictlookup($3->name, $1->pkg);
  1225  			$1->used = 1;
  1226  			$$ = oldname(s);
  1227  			break;
  1228  		}
  1229  		$$ = nod(OXDOT, $1, newname($3));
  1230  	}
  1231  
  1232  othertype:
  1233  	'[' oexpr ']' ntype
  1234  	{
  1235  		$$ = nod(OTARRAY, $2, $4);
  1236  	}
  1237  |	'[' LDDD ']' ntype
  1238  	{
  1239  		// array literal of nelem
  1240  		$$ = nod(OTARRAY, nod(ODDD, N, N), $4);
  1241  	}
  1242  |	LCHAN non_recvchantype
  1243  	{
  1244  		$$ = nod(OTCHAN, $2, N);
  1245  		$$->etype = Cboth;
  1246  	}
  1247  |	LCHAN LCOMM ntype
  1248  	{
  1249  		$$ = nod(OTCHAN, $3, N);
  1250  		$$->etype = Csend;
  1251  	}
  1252  |	LMAP '[' ntype ']' ntype
  1253  	{
  1254  		$$ = nod(OTMAP, $3, $5);
  1255  	}
  1256  |	structtype
  1257  |	interfacetype
  1258  
  1259  ptrtype:
  1260  	'*' ntype
  1261  	{
  1262  		$$ = nod(OIND, $2, N);
  1263  	}
  1264  
  1265  recvchantype:
  1266  	LCOMM LCHAN ntype
  1267  	{
  1268  		$$ = nod(OTCHAN, $3, N);
  1269  		$$->etype = Crecv;
  1270  	}
  1271  
  1272  structtype:
  1273  	LSTRUCT lbrace structdcl_list osemi '}'
  1274  	{
  1275  		$$ = nod(OTSTRUCT, N, N);
  1276  		$$->list = $3;
  1277  		fixlbrace($2);
  1278  	}
  1279  |	LSTRUCT lbrace '}'
  1280  	{
  1281  		$$ = nod(OTSTRUCT, N, N);
  1282  		fixlbrace($2);
  1283  	}
  1284  
  1285  interfacetype:
  1286  	LINTERFACE lbrace interfacedcl_list osemi '}'
  1287  	{
  1288  		$$ = nod(OTINTER, N, N);
  1289  		$$->list = $3;
  1290  		fixlbrace($2);
  1291  	}
  1292  |	LINTERFACE lbrace '}'
  1293  	{
  1294  		$$ = nod(OTINTER, N, N);
  1295  		fixlbrace($2);
  1296  	}
  1297  
  1298  /*
  1299   * function stuff
  1300   * all in one place to show how crappy it all is
  1301   */
  1302  xfndcl:
  1303  	LFUNC fndcl fnbody
  1304  	{
  1305  		$$ = $2;
  1306  		if($$ == N)
  1307  			break;
  1308  		if(noescape && $3 != nil)
  1309  			yyerror("can only use //go:noescape with external func implementations");
  1310  		$$->nbody = $3;
  1311  		$$->endlineno = lineno;
  1312  		$$->noescape = noescape;
  1313  		funcbody($$);
  1314  	}
  1315  
  1316  fndcl:
  1317  	sym '(' oarg_type_list_ocomma ')' fnres
  1318  	{
  1319  		Node *t;
  1320  
  1321  		$$ = N;
  1322  		$3 = checkarglist($3, 1);
  1323  
  1324  		if(strcmp($1->name, "init") == 0) {
  1325  			$1 = renameinit();
  1326  			if($3 != nil || $5 != nil)
  1327  				yyerror("func init must have no arguments and no return values");
  1328  		}
  1329  		if(strcmp(localpkg->name, "main") == 0 && strcmp($1->name, "main") == 0) {
  1330  			if($3 != nil || $5 != nil)
  1331  				yyerror("func main must have no arguments and no return values");
  1332  		}
  1333  
  1334  		t = nod(OTFUNC, N, N);
  1335  		t->list = $3;
  1336  		t->rlist = $5;
  1337  
  1338  		$$ = nod(ODCLFUNC, N, N);
  1339  		$$->nname = newname($1);
  1340  		$$->nname->defn = $$;
  1341  		$$->nname->ntype = t;		// TODO: check if nname already has an ntype
  1342  		declare($$->nname, PFUNC);
  1343  
  1344  		funchdr($$);
  1345  	}
  1346  |	'(' oarg_type_list_ocomma ')' sym '(' oarg_type_list_ocomma ')' fnres
  1347  	{
  1348  		Node *rcvr, *t;
  1349  
  1350  		$$ = N;
  1351  		$2 = checkarglist($2, 0);
  1352  		$6 = checkarglist($6, 1);
  1353  
  1354  		if($2 == nil) {
  1355  			yyerror("method has no receiver");
  1356  			break;
  1357  		}
  1358  		if($2->next != nil) {
  1359  			yyerror("method has multiple receivers");
  1360  			break;
  1361  		}
  1362  		rcvr = $2->n;
  1363  		if(rcvr->op != ODCLFIELD) {
  1364  			yyerror("bad receiver in method");
  1365  			break;
  1366  		}
  1367  		if(rcvr->right->op == OTPAREN || (rcvr->right->op == OIND && rcvr->right->left->op == OTPAREN))
  1368  			yyerror("cannot parenthesize receiver type");
  1369  
  1370  		t = nod(OTFUNC, rcvr, N);
  1371  		t->list = $6;
  1372  		t->rlist = $8;
  1373  
  1374  		$$ = nod(ODCLFUNC, N, N);
  1375  		$$->shortname = newname($4);
  1376  		$$->nname = methodname1($$->shortname, rcvr->right);
  1377  		$$->nname->defn = $$;
  1378  		$$->nname->ntype = t;
  1379  		$$->nname->nointerface = nointerface;
  1380  		declare($$->nname, PFUNC);
  1381  
  1382  		funchdr($$);
  1383  	}
  1384  
  1385  hidden_fndcl:
  1386  	hidden_pkg_importsym '(' ohidden_funarg_list ')' ohidden_funres
  1387  	{
  1388  		Sym *s;
  1389  		Type *t;
  1390  
  1391  		$$ = N;
  1392  
  1393  		s = $1;
  1394  		t = functype(N, $3, $5);
  1395  
  1396  		importsym(s, ONAME);
  1397  		if(s->def != N && s->def->op == ONAME) {
  1398  			if(eqtype(t, s->def->type)) {
  1399  				dclcontext = PDISCARD;  // since we skip funchdr below
  1400  				break;
  1401  			}
  1402  			yyerror("inconsistent definition for func %S during import\n\t%T\n\t%T", s, s->def->type, t);
  1403  		}
  1404  
  1405  		$$ = newname(s);
  1406  		$$->type = t;
  1407  		declare($$, PFUNC);
  1408  
  1409  		funchdr($$);
  1410  	}
  1411  |	'(' hidden_funarg_list ')' sym '(' ohidden_funarg_list ')' ohidden_funres
  1412  	{
  1413  		$$ = methodname1(newname($4), $2->n->right); 
  1414  		$$->type = functype($2->n, $6, $8);
  1415  
  1416  		checkwidth($$->type);
  1417  		addmethod($4, $$->type, 0, nointerface);
  1418  		nointerface = 0;
  1419  		funchdr($$);
  1420  		
  1421  		// inl.c's inlnode in on a dotmeth node expects to find the inlineable body as
  1422  		// (dotmeth's type)->nname->inl, and dotmeth's type has been pulled
  1423  		// out by typecheck's lookdot as this $$->ttype.  So by providing
  1424  		// this back link here we avoid special casing there.
  1425  		$$->type->nname = $$;
  1426  	}
  1427  
  1428  fntype:
  1429  	LFUNC '(' oarg_type_list_ocomma ')' fnres
  1430  	{
  1431  		$3 = checkarglist($3, 1);
  1432  		$$ = nod(OTFUNC, N, N);
  1433  		$$->list = $3;
  1434  		$$->rlist = $5;
  1435  	}
  1436  
  1437  fnbody:
  1438  	{
  1439  		$$ = nil;
  1440  	}
  1441  |	'{' stmt_list '}'
  1442  	{
  1443  		$$ = $2;
  1444  		if($$ == nil)
  1445  			$$ = list1(nod(OEMPTY, N, N));
  1446  	}
  1447  
  1448  fnres:
  1449  	%prec NotParen
  1450  	{
  1451  		$$ = nil;
  1452  	}
  1453  |	fnret_type
  1454  	{
  1455  		$$ = list1(nod(ODCLFIELD, N, $1));
  1456  	}
  1457  |	'(' oarg_type_list_ocomma ')'
  1458  	{
  1459  		$2 = checkarglist($2, 0);
  1460  		$$ = $2;
  1461  	}
  1462  
  1463  fnlitdcl:
  1464  	fntype
  1465  	{
  1466  		closurehdr($1);
  1467  	}
  1468  
  1469  fnliteral:
  1470  	fnlitdcl lbrace stmt_list '}'
  1471  	{
  1472  		$$ = closurebody($3);
  1473  		fixlbrace($2);
  1474  	}
  1475  |	fnlitdcl error
  1476  	{
  1477  		$$ = closurebody(nil);
  1478  	}
  1479  
  1480  /*
  1481   * lists of things
  1482   * note that they are left recursive
  1483   * to conserve yacc stack. they need to
  1484   * be reversed to interpret correctly
  1485   */
  1486  xdcl_list:
  1487  	{
  1488  		$$ = nil;
  1489  	}
  1490  |	xdcl_list xdcl ';'
  1491  	{
  1492  		$$ = concat($1, $2);
  1493  		if(nsyntaxerrors == 0)
  1494  			testdclstack();
  1495  		nointerface = 0;
  1496  		noescape = 0;
  1497  	}
  1498  
  1499  vardcl_list:
  1500  	vardcl
  1501  |	vardcl_list ';' vardcl
  1502  	{
  1503  		$$ = concat($1, $3);
  1504  	}
  1505  
  1506  constdcl_list:
  1507  	constdcl1
  1508  |	constdcl_list ';' constdcl1
  1509  	{
  1510  		$$ = concat($1, $3);
  1511  	}
  1512  
  1513  typedcl_list:
  1514  	typedcl
  1515  	{
  1516  		$$ = list1($1);
  1517  	}
  1518  |	typedcl_list ';' typedcl
  1519  	{
  1520  		$$ = list($1, $3);
  1521  	}
  1522  
  1523  structdcl_list:
  1524  	structdcl
  1525  |	structdcl_list ';' structdcl
  1526  	{
  1527  		$$ = concat($1, $3);
  1528  	}
  1529  
  1530  interfacedcl_list:
  1531  	interfacedcl
  1532  	{
  1533  		$$ = list1($1);
  1534  	}
  1535  |	interfacedcl_list ';' interfacedcl
  1536  	{
  1537  		$$ = list($1, $3);
  1538  	}
  1539  
  1540  structdcl:
  1541  	new_name_list ntype oliteral
  1542  	{
  1543  		NodeList *l;
  1544  
  1545  		Node *n;
  1546  		l = $1;
  1547  		if(l == nil) {
  1548  			// ? symbol, during import (list1(N) == nil)
  1549  			n = $2;
  1550  			if(n->op == OIND)
  1551  				n = n->left;
  1552  			n = embedded(n->sym, importpkg);
  1553  			n->right = $2;
  1554  			n->val = $3;
  1555  			$$ = list1(n);
  1556  			break;
  1557  		}
  1558  
  1559  		for(l=$1; l; l=l->next) {
  1560  			l->n = nod(ODCLFIELD, l->n, $2);
  1561  			l->n->val = $3;
  1562  		}
  1563  	}
  1564  |	embed oliteral
  1565  	{
  1566  		$1->val = $2;
  1567  		$$ = list1($1);
  1568  	}
  1569  |	'(' embed ')' oliteral
  1570  	{
  1571  		$2->val = $4;
  1572  		$$ = list1($2);
  1573  		yyerror("cannot parenthesize embedded type");
  1574  	}
  1575  |	'*' embed oliteral
  1576  	{
  1577  		$2->right = nod(OIND, $2->right, N);
  1578  		$2->val = $3;
  1579  		$$ = list1($2);
  1580  	}
  1581  |	'(' '*' embed ')' oliteral
  1582  	{
  1583  		$3->right = nod(OIND, $3->right, N);
  1584  		$3->val = $5;
  1585  		$$ = list1($3);
  1586  		yyerror("cannot parenthesize embedded type");
  1587  	}
  1588  |	'*' '(' embed ')' oliteral
  1589  	{
  1590  		$3->right = nod(OIND, $3->right, N);
  1591  		$3->val = $5;
  1592  		$$ = list1($3);
  1593  		yyerror("cannot parenthesize embedded type");
  1594  	}
  1595  
  1596  packname:
  1597  	LNAME
  1598  	{
  1599  		Node *n;
  1600  
  1601  		$$ = $1;
  1602  		n = oldname($1);
  1603  		if(n->pack != N)
  1604  			n->pack->used = 1;
  1605  	}
  1606  |	LNAME '.' sym
  1607  	{
  1608  		Pkg *pkg;
  1609  
  1610  		if($1->def == N || $1->def->op != OPACK) {
  1611  			yyerror("%S is not a package", $1);
  1612  			pkg = localpkg;
  1613  		} else {
  1614  			$1->def->used = 1;
  1615  			pkg = $1->def->pkg;
  1616  		}
  1617  		$$ = restrictlookup($3->name, pkg);
  1618  	}
  1619  
  1620  embed:
  1621  	packname
  1622  	{
  1623  		$$ = embedded($1, localpkg);
  1624  	}
  1625  
  1626  interfacedcl:
  1627  	new_name indcl
  1628  	{
  1629  		$$ = nod(ODCLFIELD, $1, $2);
  1630  		ifacedcl($$);
  1631  	}
  1632  |	packname
  1633  	{
  1634  		$$ = nod(ODCLFIELD, N, oldname($1));
  1635  	}
  1636  |	'(' packname ')'
  1637  	{
  1638  		$$ = nod(ODCLFIELD, N, oldname($2));
  1639  		yyerror("cannot parenthesize embedded type");
  1640  	}
  1641  
  1642  indcl:
  1643  	'(' oarg_type_list_ocomma ')' fnres
  1644  	{
  1645  		// without func keyword
  1646  		$2 = checkarglist($2, 1);
  1647  		$$ = nod(OTFUNC, fakethis(), N);
  1648  		$$->list = $2;
  1649  		$$->rlist = $4;
  1650  	}
  1651  
  1652  /*
  1653   * function arguments.
  1654   */
  1655  arg_type:
  1656  	name_or_type
  1657  |	sym name_or_type
  1658  	{
  1659  		$$ = nod(ONONAME, N, N);
  1660  		$$->sym = $1;
  1661  		$$ = nod(OKEY, $$, $2);
  1662  	}
  1663  |	sym dotdotdot
  1664  	{
  1665  		$$ = nod(ONONAME, N, N);
  1666  		$$->sym = $1;
  1667  		$$ = nod(OKEY, $$, $2);
  1668  	}
  1669  |	dotdotdot
  1670  
  1671  arg_type_list:
  1672  	arg_type
  1673  	{
  1674  		$$ = list1($1);
  1675  	}
  1676  |	arg_type_list ',' arg_type
  1677  	{
  1678  		$$ = list($1, $3);
  1679  	}
  1680  
  1681  oarg_type_list_ocomma:
  1682  	{
  1683  		$$ = nil;
  1684  	}
  1685  |	arg_type_list ocomma
  1686  	{
  1687  		$$ = $1;
  1688  	}
  1689  
  1690  /*
  1691   * statement
  1692   */
  1693  stmt:
  1694  	{
  1695  		$$ = N;
  1696  	}
  1697  |	compound_stmt
  1698  |	common_dcl
  1699  	{
  1700  		$$ = liststmt($1);
  1701  	}
  1702  |	non_dcl_stmt
  1703  |	error
  1704  	{
  1705  		$$ = N;
  1706  	}
  1707  
  1708  non_dcl_stmt:
  1709  	simple_stmt
  1710  |	for_stmt
  1711  |	switch_stmt
  1712  |	select_stmt
  1713  |	if_stmt
  1714  |	labelname ':'
  1715  	{
  1716  		$1 = nod(OLABEL, $1, N);
  1717  		$1->sym = dclstack;  // context, for goto restrictions
  1718  	}
  1719  	stmt
  1720  	{
  1721  		NodeList *l;
  1722  
  1723  		$1->defn = $4;
  1724  		l = list1($1);
  1725  		if($4)
  1726  			l = list(l, $4);
  1727  		$$ = liststmt(l);
  1728  	}
  1729  |	LFALL
  1730  	{
  1731  		// will be converted to OFALL
  1732  		$$ = nod(OXFALL, N, N);
  1733  	}
  1734  |	LBREAK onew_name
  1735  	{
  1736  		$$ = nod(OBREAK, $2, N);
  1737  	}
  1738  |	LCONTINUE onew_name
  1739  	{
  1740  		$$ = nod(OCONTINUE, $2, N);
  1741  	}
  1742  |	LGO pseudocall
  1743  	{
  1744  		$$ = nod(OPROC, $2, N);
  1745  	}
  1746  |	LDEFER pseudocall
  1747  	{
  1748  		$$ = nod(ODEFER, $2, N);
  1749  	}
  1750  |	LGOTO new_name
  1751  	{
  1752  		$$ = nod(OGOTO, $2, N);
  1753  		$$->sym = dclstack;  // context, for goto restrictions
  1754  	}
  1755  |	LRETURN oexpr_list
  1756  	{
  1757  		$$ = nod(ORETURN, N, N);
  1758  		$$->list = $2;
  1759  		if($$->list == nil && curfn != N) {
  1760  			NodeList *l;
  1761  
  1762  			for(l=curfn->dcl; l; l=l->next) {
  1763  				if(l->n->class == PPARAM)
  1764  					continue;
  1765  				if(l->n->class != PPARAMOUT)
  1766  					break;
  1767  				if(l->n->sym->def != l->n)
  1768  					yyerror("%s is shadowed during return", l->n->sym->name);
  1769  			}
  1770  		}
  1771  	}
  1772  
  1773  stmt_list:
  1774  	stmt
  1775  	{
  1776  		$$ = nil;
  1777  		if($1 != N)
  1778  			$$ = list1($1);
  1779  	}
  1780  |	stmt_list ';' stmt
  1781  	{
  1782  		$$ = $1;
  1783  		if($3 != N)
  1784  			$$ = list($$, $3);
  1785  	}
  1786  
  1787  new_name_list:
  1788  	new_name
  1789  	{
  1790  		$$ = list1($1);
  1791  	}
  1792  |	new_name_list ',' new_name
  1793  	{
  1794  		$$ = list($1, $3);
  1795  	}
  1796  
  1797  dcl_name_list:
  1798  	dcl_name
  1799  	{
  1800  		$$ = list1($1);
  1801  	}
  1802  |	dcl_name_list ',' dcl_name
  1803  	{
  1804  		$$ = list($1, $3);
  1805  	}
  1806  
  1807  expr_list:
  1808  	expr
  1809  	{
  1810  		$$ = list1($1);
  1811  	}
  1812  |	expr_list ',' expr
  1813  	{
  1814  		$$ = list($1, $3);
  1815  	}
  1816  
  1817  expr_or_type_list:
  1818  	expr_or_type
  1819  	{
  1820  		$$ = list1($1);
  1821  	}
  1822  |	expr_or_type_list ',' expr_or_type
  1823  	{
  1824  		$$ = list($1, $3);
  1825  	}
  1826  
  1827  /*
  1828   * list of combo of keyval and val
  1829   */
  1830  keyval_list:
  1831  	keyval
  1832  	{
  1833  		$$ = list1($1);
  1834  	}
  1835  |	bare_complitexpr
  1836  	{
  1837  		$$ = list1($1);
  1838  	}
  1839  |	keyval_list ',' keyval
  1840  	{
  1841  		$$ = list($1, $3);
  1842  	}
  1843  |	keyval_list ',' bare_complitexpr
  1844  	{
  1845  		$$ = list($1, $3);
  1846  	}
  1847  
  1848  braced_keyval_list:
  1849  	{
  1850  		$$ = nil;
  1851  	}
  1852  |	keyval_list ocomma
  1853  	{
  1854  		$$ = $1;
  1855  	}
  1856  
  1857  /*
  1858   * optional things
  1859   */
  1860  osemi:
  1861  |	';'
  1862  
  1863  ocomma:
  1864  |	','
  1865  
  1866  oexpr:
  1867  	{
  1868  		$$ = N;
  1869  	}
  1870  |	expr
  1871  
  1872  oexpr_list:
  1873  	{
  1874  		$$ = nil;
  1875  	}
  1876  |	expr_list
  1877  
  1878  osimple_stmt:
  1879  	{
  1880  		$$ = N;
  1881  	}
  1882  |	simple_stmt
  1883  
  1884  ohidden_funarg_list:
  1885  	{
  1886  		$$ = nil;
  1887  	}
  1888  |	hidden_funarg_list
  1889  
  1890  ohidden_structdcl_list:
  1891  	{
  1892  		$$ = nil;
  1893  	}
  1894  |	hidden_structdcl_list
  1895  
  1896  ohidden_interfacedcl_list:
  1897  	{
  1898  		$$ = nil;
  1899  	}
  1900  |	hidden_interfacedcl_list
  1901  
  1902  oliteral:
  1903  	{
  1904  		$$.ctype = CTxxx;
  1905  	}
  1906  |	LLITERAL
  1907  
  1908  /*
  1909   * import syntax from package header
  1910   */
  1911  hidden_import:
  1912  	LIMPORT LNAME LLITERAL ';'
  1913  	{
  1914  		importimport($2, $3.u.sval);
  1915  	}
  1916  |	LVAR hidden_pkg_importsym hidden_type ';'
  1917  	{
  1918  		importvar($2, $3);
  1919  	}
  1920  |	LCONST hidden_pkg_importsym '=' hidden_constant ';'
  1921  	{
  1922  		importconst($2, types[TIDEAL], $4);
  1923  	}
  1924  |	LCONST hidden_pkg_importsym hidden_type '=' hidden_constant ';'
  1925  	{
  1926  		importconst($2, $3, $5);
  1927  	}
  1928  |	LTYPE hidden_pkgtype hidden_type ';'
  1929  	{
  1930  		importtype($2, $3);
  1931  	}
  1932  |	LFUNC hidden_fndcl fnbody ';'
  1933  	{
  1934  		if($2 == N) {
  1935  			dclcontext = PEXTERN;  // since we skip the funcbody below
  1936  			break;
  1937  		}
  1938  
  1939  		$2->inl = $3;
  1940  
  1941  		funcbody($2);
  1942  		importlist = list(importlist, $2);
  1943  
  1944  		if(debug['E']) {
  1945  			print("import [%Z] func %lN \n", importpkg->path, $2);
  1946  			if(debug['m'] > 2 && $2->inl)
  1947  				print("inl body:%+H\n", $2->inl);
  1948  		}
  1949  	}
  1950  
  1951  hidden_pkg_importsym:
  1952  	hidden_importsym
  1953  	{
  1954  		$$ = $1;
  1955  		structpkg = $$->pkg;
  1956  	}
  1957  
  1958  hidden_pkgtype:
  1959  	hidden_pkg_importsym
  1960  	{
  1961  		$$ = pkgtype($1);
  1962  		importsym($1, OTYPE);
  1963  	}
  1964  
  1965  /*
  1966   *  importing types
  1967   */
  1968  
  1969  hidden_type:
  1970  	hidden_type_misc
  1971  |	hidden_type_recv_chan
  1972  |	hidden_type_func
  1973  
  1974  hidden_type_non_recv_chan:
  1975  	hidden_type_misc
  1976  |	hidden_type_func
  1977  
  1978  hidden_type_misc:
  1979  	hidden_importsym
  1980  	{
  1981  		$$ = pkgtype($1);
  1982  	}
  1983  |	LNAME
  1984  	{
  1985  		// predefined name like uint8
  1986  		$1 = pkglookup($1->name, builtinpkg);
  1987  		if($1->def == N || $1->def->op != OTYPE) {
  1988  			yyerror("%s is not a type", $1->name);
  1989  			$$ = T;
  1990  		} else
  1991  			$$ = $1->def->type;
  1992  	}
  1993  |	'[' ']' hidden_type
  1994  	{
  1995  		$$ = aindex(N, $3);
  1996  	}
  1997  |	'[' LLITERAL ']' hidden_type
  1998  	{
  1999  		$$ = aindex(nodlit($2), $4);
  2000  	}
  2001  |	LMAP '[' hidden_type ']' hidden_type
  2002  	{
  2003  		$$ = maptype($3, $5);
  2004  	}
  2005  |	LSTRUCT '{' ohidden_structdcl_list '}'
  2006  	{
  2007  		$$ = tostruct($3);
  2008  	}
  2009  |	LINTERFACE '{' ohidden_interfacedcl_list '}'
  2010  	{
  2011  		$$ = tointerface($3);
  2012  	}
  2013  |	'*' hidden_type
  2014  	{
  2015  		$$ = ptrto($2);
  2016  	}
  2017  |	LCHAN hidden_type_non_recv_chan
  2018  	{
  2019  		$$ = typ(TCHAN);
  2020  		$$->type = $2;
  2021  		$$->chan = Cboth;
  2022  	}
  2023  |	LCHAN '(' hidden_type_recv_chan ')'
  2024  	{
  2025  		$$ = typ(TCHAN);
  2026  		$$->type = $3;
  2027  		$$->chan = Cboth;
  2028  	}
  2029  |	LCHAN LCOMM hidden_type
  2030  	{
  2031  		$$ = typ(TCHAN);
  2032  		$$->type = $3;
  2033  		$$->chan = Csend;
  2034  	}
  2035  
  2036  hidden_type_recv_chan:
  2037  	LCOMM LCHAN hidden_type
  2038  	{
  2039  		$$ = typ(TCHAN);
  2040  		$$->type = $3;
  2041  		$$->chan = Crecv;
  2042  	}
  2043  
  2044  hidden_type_func:
  2045  	LFUNC '(' ohidden_funarg_list ')' ohidden_funres
  2046  	{
  2047  		$$ = functype(nil, $3, $5);
  2048  	}
  2049  
  2050  hidden_funarg:
  2051  	sym hidden_type oliteral
  2052  	{
  2053  		$$ = nod(ODCLFIELD, N, typenod($2));
  2054  		if($1)
  2055  			$$->left = newname($1);
  2056  		$$->val = $3;
  2057  	}
  2058  |	sym LDDD hidden_type oliteral
  2059  	{
  2060  		Type *t;
  2061  	
  2062  		t = typ(TARRAY);
  2063  		t->bound = -1;
  2064  		t->type = $3;
  2065  
  2066  		$$ = nod(ODCLFIELD, N, typenod(t));
  2067  		if($1)
  2068  			$$->left = newname($1);
  2069  		$$->isddd = 1;
  2070  		$$->val = $4;
  2071  	}
  2072  
  2073  hidden_structdcl:
  2074  	sym hidden_type oliteral
  2075  	{
  2076  		Sym *s;
  2077  		Pkg *p;
  2078  
  2079  		if($1 != S && strcmp($1->name, "?") != 0) {
  2080  			$$ = nod(ODCLFIELD, newname($1), typenod($2));
  2081  			$$->val = $3;
  2082  		} else {
  2083  			s = $2->sym;
  2084  			if(s == S && isptr[$2->etype])
  2085  				s = $2->type->sym;
  2086  			p = importpkg;
  2087  			if($1 != S)
  2088  				p = $1->pkg;
  2089  			$$ = embedded(s, p);
  2090  			$$->right = typenod($2);
  2091  			$$->val = $3;
  2092  		}
  2093  	}
  2094  
  2095  hidden_interfacedcl:
  2096  	sym '(' ohidden_funarg_list ')' ohidden_funres
  2097  	{
  2098  		$$ = nod(ODCLFIELD, newname($1), typenod(functype(fakethis(), $3, $5)));
  2099  	}
  2100  |	hidden_type
  2101  	{
  2102  		$$ = nod(ODCLFIELD, N, typenod($1));
  2103  	}
  2104  
  2105  ohidden_funres:
  2106  	{
  2107  		$$ = nil;
  2108  	}
  2109  |	hidden_funres
  2110  
  2111  hidden_funres:
  2112  	'(' ohidden_funarg_list ')'
  2113  	{
  2114  		$$ = $2;
  2115  	}
  2116  |	hidden_type
  2117  	{
  2118  		$$ = list1(nod(ODCLFIELD, N, typenod($1)));
  2119  	}
  2120  
  2121  /*
  2122   *  importing constants
  2123   */
  2124  
  2125  hidden_literal:
  2126  	LLITERAL
  2127  	{
  2128  		$$ = nodlit($1);
  2129  	}
  2130  |	'-' LLITERAL
  2131  	{
  2132  		$$ = nodlit($2);
  2133  		switch($$->val.ctype){
  2134  		case CTINT:
  2135  		case CTRUNE:
  2136  			mpnegfix($$->val.u.xval);
  2137  			break;
  2138  		case CTFLT:
  2139  			mpnegflt($$->val.u.fval);
  2140  			break;
  2141  		default:
  2142  			yyerror("bad negated constant");
  2143  		}
  2144  	}
  2145  |	sym
  2146  	{
  2147  		$$ = oldname(pkglookup($1->name, builtinpkg));
  2148  		if($$->op != OLITERAL)
  2149  			yyerror("bad constant %S", $$->sym);
  2150  	}
  2151  
  2152  hidden_constant:
  2153  	hidden_literal
  2154  |	'(' hidden_literal '+' hidden_literal ')'
  2155  	{
  2156  		if($2->val.ctype == CTRUNE && $4->val.ctype == CTINT) {
  2157  			$$ = $2;
  2158  			mpaddfixfix($2->val.u.xval, $4->val.u.xval, 0);
  2159  			break;
  2160  		}
  2161  		$4->val.u.cval->real = $4->val.u.cval->imag;
  2162  		mpmovecflt(&$4->val.u.cval->imag, 0.0);
  2163  		$$ = nodcplxlit($2->val, $4->val);
  2164  	}
  2165  
  2166  hidden_import_list:
  2167  |	hidden_import_list hidden_import
  2168  
  2169  hidden_funarg_list:
  2170  	hidden_funarg
  2171  	{
  2172  		$$ = list1($1);
  2173  	}
  2174  |	hidden_funarg_list ',' hidden_funarg
  2175  	{
  2176  		$$ = list($1, $3);
  2177  	}
  2178  
  2179  hidden_structdcl_list:
  2180  	hidden_structdcl
  2181  	{
  2182  		$$ = list1($1);
  2183  	}
  2184  |	hidden_structdcl_list ';' hidden_structdcl
  2185  	{
  2186  		$$ = list($1, $3);
  2187  	}
  2188  
  2189  hidden_interfacedcl_list:
  2190  	hidden_interfacedcl
  2191  	{
  2192  		$$ = list1($1);
  2193  	}
  2194  |	hidden_interfacedcl_list ';' hidden_interfacedcl
  2195  	{
  2196  		$$ = list($1, $3);
  2197  	}
  2198  
  2199  %%
  2200  
  2201  static void
  2202  fixlbrace(int lbr)
  2203  {
  2204  	// If the opening brace was an LBODY,
  2205  	// set up for another one now that we're done.
  2206  	// See comment in lex.c about loophack.
  2207  	if(lbr == LBODY)
  2208  		loophack = 1;
  2209  }
  2210