From: Rico Tzschichholz <ricotz@ubuntu.com>
Date: Mon, 24 Jan 2022 09:17:46 +0000 (+0100)
Subject: codegen: Access of stack allocated struct is guaranteed to be non null
X-Git-Tag: 0.55.2~14
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ca3da69b2bda18b8b081c2dae48f2ccff93f165a;p=thirdparty%2Fvala.git

codegen: Access of stack allocated struct is guaranteed to be non null

Found by -Werror=address with GCC 12

See https://gitlab.gnome.org/GNOME/vala/issues/1282
---

diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 9ebcfbac6..2e34003f1 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -5593,6 +5593,8 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
 			innercexpr = new CCodeUnaryExpression (CCodeUnaryOperator.ADDRESS_OF, innercexpr);
 		}
 		set_cvalue (expr, new CCodeCastExpression (innercexpr, get_ccode_name (expr.type_reference)));
+		//TODO Use get_non_null (expr.inner.target_value)
+		((GLibValue) expr.target_value).non_null = expr.is_non_null ();
 
 		if (expr.type_reference is DelegateType) {
 			var target = get_delegate_target (expr.inner);
diff --git a/tests/structs/bug777194.c-expected b/tests/structs/bug777194.c-expected
index 927043755..055c37c70 100644
--- a/tests/structs/bug777194.c-expected
+++ b/tests/structs/bug777194.c-expected
@@ -238,7 +238,7 @@ _vala_main (void)
 	_tmp4_ = tu;
 	_tmp4__length1 = tu_length1;
 	bar (_tmp4_, (gint) _tmp4__length1);
-	_tmp5_ = (((guint8*) (&fstack)) != NULL) ? _vala_array_dup1 ((guint8*) (&fstack), sizeof (Foo) / sizeof (guint8)) : ((guint8*) (&fstack));
+	_tmp5_ = _vala_array_dup1 ((guint8*) (&fstack), sizeof (Foo) / sizeof (guint8));
 	_tmp5__length1 = sizeof (Foo) / sizeof (guint8);
 	to = (g_free (to), NULL);
 	to = _tmp5_;
@@ -263,7 +263,7 @@ _vala_main (void)
 	_tmp11__length1 = tu_length1;
 	bar (_tmp11_, (gint) _tmp11__length1);
 	_tmp12_ = fstack;
-	_tmp13_ = (((guint8*) (&_tmp12_)) != NULL) ? _vala_array_dup2 ((guint8*) (&_tmp12_), sizeof (Foo) / sizeof (guint8)) : ((guint8*) (&_tmp12_));
+	_tmp13_ = _vala_array_dup2 ((guint8*) (&_tmp12_), sizeof (Foo) / sizeof (guint8));
 	_tmp13__length1 = sizeof (Foo) / sizeof (guint8);
 	to = (g_free (to), NULL);
 	to = _tmp13_;
@@ -310,7 +310,7 @@ _vala_main (void)
 	_tmp22_ = tu;
 	_tmp22__length1 = tu_length1;
 	_vala_assert (_tmp22__length1 == 4, "tu.length == 4");
-	_tmp23_ = (((guint8*) (&i32)) != NULL) ? _vala_array_dup4 ((guint8*) (&i32), sizeof (gint32) / sizeof (guint8)) : ((guint8*) (&i32));
+	_tmp23_ = _vala_array_dup4 ((guint8*) (&i32), sizeof (gint32) / sizeof (guint8));
 	_tmp23__length1 = sizeof (gint32) / sizeof (guint8);
 	to = (g_free (to), NULL);
 	to = _tmp23_;
@@ -332,7 +332,7 @@ _vala_main (void)
 	_tmp26_ = tu;
 	_tmp26__length1 = tu_length1;
 	_vala_assert (_tmp26__length1 == 8, "tu.length == 8");
-	_tmp27_ = (((guint8*) (&u64)) != NULL) ? _vala_array_dup5 ((guint8*) (&u64), sizeof (guint64) / sizeof (guint8)) : ((guint8*) (&u64));
+	_tmp27_ = _vala_array_dup5 ((guint8*) (&u64), sizeof (guint64) / sizeof (guint8));
 	_tmp27__length1 = sizeof (guint64) / sizeof (guint8);
 	to = (g_free (to), NULL);
 	to = _tmp27_;
diff --git a/vala/valaaddressofexpression.vala b/vala/valaaddressofexpression.vala
index ff542835b..dbe9cff1a 100644
--- a/vala/valaaddressofexpression.vala
+++ b/vala/valaaddressofexpression.vala
@@ -82,6 +82,10 @@ public class Vala.AddressofExpression : Expression {
 		return inner.is_accessible (sym);
 	}
 
+	public override bool is_non_null () {
+		return inner.is_non_null ();
+	}
+
 	public override bool check (CodeContext context) {
 		if (checked) {
 			return !error;
diff --git a/vala/valamemberaccess.vala b/vala/valamemberaccess.vala
index d27a4266a..f083da911 100644
--- a/vala/valamemberaccess.vala
+++ b/vala/valamemberaccess.vala
@@ -203,7 +203,12 @@ public class Vala.MemberAccess : Expression {
 		if (c != null) {
 			return (c is EnumValue || !c.type_reference.nullable);
 		} else if (l != null) {
-			return (l.variable_type is ArrayType && ((ArrayType) l.variable_type).inline_allocated);
+			unowned DataType type = l.variable_type;
+			if (type is ArrayType) {
+				return ((ArrayType) type).inline_allocated;
+			} else {
+				return type.is_real_non_null_struct_type () || type.is_non_null_simple_type ();
+			}
 		} else if (m != null) {
 			return (m.binding == MemberBinding.STATIC || prototype_access);
 		} else {