[C] Fix ICE for composite type for structs with unsigned bitfields [PR113492]
Checks
Commit Message
C23: Fix ICE for composite type for structs with unsigned bitfields [PR113492]
This patch fixes a bug when forming a composite type from structs that
contain an unsigned bitfield declared with int while using -funsigned-bitfields.
In such structs the unsigned integer type was not compatible to the
regular unsigned integer type used elsewhere in the C FE.
PR c/113492
gcc/c:
* c-decl.cc (grokdeclarator): Use c_common_unsigned_type instead of
unsigned_type_for to create the unsigned type for bitfields declared
with int when using -funsigned-bitfields.
gcc/testsuite:
* gcc.dg/pr113492.c: New test.
Comments
On Sat, 20 Jan 2024, Martin Uecker wrote:
> C23: Fix ICE for composite type for structs with unsigned bitfields [PR113492]
>
> This patch fixes a bug when forming a composite type from structs that
> contain an unsigned bitfield declared with int while using -funsigned-bitfields.
> In such structs the unsigned integer type was not compatible to the
> regular unsigned integer type used elsewhere in the C FE.
>
> PR c/113492
>
> gcc/c:
> * c-decl.cc (grokdeclarator): Use c_common_unsigned_type instead of
> unsigned_type_for to create the unsigned type for bitfields declared
> with int when using -funsigned-bitfields.
>
> gcc/testsuite:
> * gcc.dg/pr113492.c: New test.
OK.
@@ -6947,7 +6947,7 @@ grokdeclarator (const struct c_declarator *declarator,
"signed". */
if (bitfield && !flag_signed_bitfields && !declspecs->explicit_signed_p
&& TREE_CODE (type) == INTEGER_TYPE)
- type = unsigned_type_for (type);
+ type = c_common_unsigned_type (type);
/* Figure out the type qualifiers for the declaration. There are
two ways a declaration can become qualified. One is something
new file mode 100644
@@ -0,0 +1,43 @@
+/* PR 113492
+ * { dg-do compile }
+ * { dg-options "-std=c23 -funsigned-bitfields" } */
+
+struct foo {
+ int i : 3;
+} i;
+
+void test()
+{
+ struct foo {
+ unsigned i : 3;
+ } u;
+
+ 1 ? i : u;
+ 1 ? u : i;
+}
+
+struct bar {
+ unsigned i : 3;
+} u;
+
+void test2()
+{
+ struct bar {
+ int i : 3;
+ } i;
+
+ 1 ? i : u;
+ 1 ? u : i;
+}
+
+void test3()
+{
+ typedef int myint;
+ struct bar {
+ myint i : 3;
+ } i;
+
+ 1 ? i : u;
+ 1 ? u : i;
+}
+