github.com/riscv/riscv-go@v0.0.0-20200123204226-124ebd6fcc8e/misc/cgo/test/issue3261.go (about)

     1  // Copyright 2012 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  package cgotest
     6  
     7  /*
     8  // libgcc on ARM might be compiled as thumb code, but our 5l
     9  // can't handle that, so we have to disable this test on arm.
    10  #ifdef __ARMEL__
    11  #include <stdio.h>
    12  int vabs(int x) {
    13  	puts("testLibgcc is disabled on ARM because 5l cannot handle thumb library.");
    14  	return (x < 0) ? -x : x;
    15  }
    16  #elif defined(__arm64__) && defined(__clang__)
    17  #include <stdio.h>
    18  int vabs(int x) {
    19  	puts("testLibgcc is disabled on ARM64 with clang due to lack of libgcc.");
    20  	return (x < 0) ? -x : x;
    21  }
    22  #else
    23  int __absvsi2(int); // dummy prototype for libgcc function
    24  // we shouldn't name the function abs, as gcc might use
    25  // the builtin one.
    26  int vabs(int x) { return __absvsi2(x); }
    27  #endif
    28  */
    29  import "C"
    30  
    31  import "testing"
    32  
    33  func testLibgcc(t *testing.T) {
    34  	var table = []struct {
    35  		in, out C.int
    36  	}{
    37  		{0, 0},
    38  		{1, 1},
    39  		{-42, 42},
    40  		{1000300, 1000300},
    41  		{1 - 1<<31, 1<<31 - 1},
    42  	}
    43  	for _, v := range table {
    44  		if o := C.vabs(v.in); o != v.out {
    45  			t.Fatalf("abs(%d) got %d, should be %d", v.in, o, v.out)
    46  			return
    47  		}
    48  	}
    49  }