cxgo: do not flatten blocks with decls; fixes #42

c_stmt.go

@@ -710,11 +710,21 @@ func (g *translator) cBlockCast(s CStmt) *BlockStmt {
 	return g.newBlockStmt(s)
 }
 
+func stmtHasDecl(stmts ...CStmt) bool {
+	for _, st := range stmts {
+		switch st.(type) {
+		case *CDeclStmt:
+			return true
+		}
+	}
+	return false
+}
+
 func flattenBlocks(stmts []CStmt) ([]CStmt, bool) {
 	mod := false
 	for i := 0; i < len(stmts); i++ {
 		s, ok := stmts[i].(*BlockStmt)
-		if !ok {
+		if !ok || stmtHasDecl(s.Stmts...) {
 			continue
 		}
 		arr := append([]CStmt{}, stmts[:i]...)

parse_test.go

@@ -486,6 +486,73 @@ func foo(a *int32) int32 {
 	foo(a)
 	return 1
 }
+`,
+	},
+	{
+		name: "blocks with vars",
+		src: `
+#define set(s) \
+{ int t = s;\
+}
+
+void main() {
+  int s;
+  if (0) {
+    set(s)
+    set(s)
+    set(s)
+  }
+}
+`,
+		exp: `
+func main() {
+	var s int32
+	if false {
+		{
+			var t int32 = s
+			_ = t
+		}
+		{
+			var t int32 = s
+			_ = t
+		}
+		{
+			var t int32 = s
+			_ = t
+		}
+	}
+}
+`,
+	},
+	{
+		name: "blocks no vars",
+		src: `
+#define set(s) \
+{ t = s;\
+}
+
+void main() {
+  int s, t;
+  if (0) {
+    set(s)
+    set(s)
+    set(s)
+  }
+}
+`,
+		exp: `
+func main() {
+	var (
+		s int32
+		t int32
+	)
+	_ = t
+	if false {
+		t = s
+		t = s
+		t = s
+	}
+}
 `,
 	},
 	{