cmd/cgo: fix alignment of bool.

Fixes #4417.

R=golang-dev, iant, minux.ma, bradfitz
CC=golang-dev, vova616
https://golang.org/cl/6782097

misc/cgo/test/cgo_test.go

@@ -32,5 +32,6 @@ func TestLibgcc(t *testing.T)              { testLibgcc(t) }
 func Test1635(t *testing.T)                { test1635(t) }
 func TestPrintf(t *testing.T)              { testPrintf(t) }
 func Test4029(t *testing.T)                { test4029(t) }
+func TestBoolAlign(t *testing.T)           { testBoolAlign(t) }
 
 func BenchmarkCgoCall(b *testing.B) { benchCgoCall(b) }

misc/cgo/test/issue4417.go

+// run
+
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 4417:	cmd/cgo: bool alignment/padding issue.
+// bool alignment is wrong and causing wrong arguments when calling functions.
+//
+
+package cgotest
+
+/*
+#include <stdbool.h>
+
+static int c_bool(bool a, bool b, int c, bool d, bool e)  {
+   return c;
+}
+*/
+import "C"
+import "testing"
+
+func testBoolAlign(t *testing.T) {
+	b := C.c_bool(true, true, 10, true, false)
+	if b != 10 {
+		t.Fatalf("found %d expected 10\n", b)
+	}
+	b = C.c_bool(true, true, 5, true, true)
+	if b != 5 {
+		t.Fatalf("found %d expected 5\n", b)
+	}
+	b = C.c_bool(true, true, 3, true, false)
+	if b != 3 {
+		t.Fatalf("found %d expected 3\n", b)
+	}
+	b = C.c_bool(false, false, 1, true, false)
+	if b != 1 {
+		t.Fatalf("found %d expected 1\n", b)
+	}
+	b = C.c_bool(false, true, 200, true, false)
+	if b != 200 {
+		t.Fatalf("found %d expected 200\n", b)
+	}
+}

src/cmd/cgo/gcc.go

@@ -1078,7 +1078,7 @@ func (c *typeConv) Type(dtype dwarf.Type, pos token.Pos) *Type {
 
 	case *dwarf.BoolType:
 		t.Go = c.bool
-		t.Align = c.ptrSize
+		t.Align = 1
 
 	case *dwarf.CharType:
 		if t.Size != 1 {