Re: [RFC][PATCH v1 3/4] Add testing cases for flexible array members in unions and alone in structures.
> On Apr 23, 2024, at 14:53, Joseph Myers wrote: > > On Fri, 19 Apr 2024, Qing Zhao wrote: > >> gcc/testsuite/ChangeLog: >> >> * gcc.dg/flex-array-in-union-1.c: New test. >> * gcc.dg/flex-array-in-union-2.c: New test. > > There should also be a -pedantic-errors test that these constructs get > errors with -pedantic-errors. Okay, will add. > > The tests mix two cases: flexible arrays in unions, and flexible arrays on > their own in structures. That means the test names are misleading; either > they should be renamed, or the struct tests should be split out. Okay, will update this. > > Note that "no named members" also includes the case where there are > unnamed bit-fields together with a flexible array member, so that should > be tested as well. Will add such testing cases. > > Since this patch series involves changes for both C and C++, it would be > best for the tests to be c-c++-common tests. But if that's problematic > for some reason - if there's still too much difference in behavior between > C and C++ - then there should at least be tests for C++ that are as > similar as possible to the tests for C. I tried to put these two testing cases to c-c++-common, there were some inconsistent behavior I cannot resolve at that time, I will try to fix those issue or add C++ testing cases. Thanks for the review. Qing > > -- > Joseph S. Myers > josmy...@redhat.com >
Re: [RFC][PATCH v1 3/4] Add testing cases for flexible array members in unions and alone in structures.
On Fri, 19 Apr 2024, Qing Zhao wrote: > gcc/testsuite/ChangeLog: > > * gcc.dg/flex-array-in-union-1.c: New test. > * gcc.dg/flex-array-in-union-2.c: New test. There should also be a -pedantic-errors test that these constructs get errors with -pedantic-errors. The tests mix two cases: flexible arrays in unions, and flexible arrays on their own in structures. That means the test names are misleading; either they should be renamed, or the struct tests should be split out. Note that "no named members" also includes the case where there are unnamed bit-fields together with a flexible array member, so that should be tested as well. Since this patch series involves changes for both C and C++, it would be best for the tests to be c-c++-common tests. But if that's problematic for some reason - if there's still too much difference in behavior between C and C++ - then there should at least be tests for C++ that are as similar as possible to the tests for C. -- Joseph S. Myers josmy...@redhat.com
[RFC][PATCH v1 3/4] Add testing cases for flexible array members in unions and alone in structures.
gcc/testsuite/ChangeLog:
* gcc.dg/flex-array-in-union-1.c: New test.
* gcc.dg/flex-array-in-union-2.c: New test.
---
gcc/testsuite/gcc.dg/flex-array-in-union-1.c | 37 +
gcc/testsuite/gcc.dg/flex-array-in-union-2.c | 42
2 files changed, 79 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/flex-array-in-union-1.c
create mode 100644 gcc/testsuite/gcc.dg/flex-array-in-union-2.c
diff --git a/gcc/testsuite/gcc.dg/flex-array-in-union-1.c
b/gcc/testsuite/gcc.dg/flex-array-in-union-1.c
new file mode 100644
index ..2a532d77c1dd
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/flex-array-in-union-1.c
@@ -0,0 +1,37 @@
+/* testing the correct usage of flexible array members in unions
+ and alone in structure. */
+/* { dg-do run} */
+/* { dg-options "-O2 -Wpedantic" } */
+
+union with_fam_1 {
+ int a;
+ int b[]; /* { dg-warning "flexible array member in union is a GCC
extension" } */
+};
+
+union with_fam_2 {
+ char a;
+ int b[]; /* { dg-warning "flexible array member in union is a GCC
extension" } */
+};
+
+union with_fam_3 {
+ char a[]; /* { dg-warning " flexible array member in union is a GCC
extension" } */
+ int b[]; /* { dg-warning "flexible array member in union is a GCC
extension" } */
+};
+
+struct only_fam {
+ int b[]; /* { dg-warning "flexible array member in a struct with no named
members is a GCC extension" } */
+};
+
+int main ()
+{
+ if (sizeof (union with_fam_1) != sizeof (int))
+__builtin_abort ();
+ if (sizeof (union with_fam_2) != __alignof__ (int))
+__builtin_abort ();
+ if (sizeof (union with_fam_3) != 0)
+__builtin_abort ();
+ if (sizeof (struct only_fam) != 0)
+__builtin_abort ();
+ return 0;
+}
+
diff --git a/gcc/testsuite/gcc.dg/flex-array-in-union-2.c
b/gcc/testsuite/gcc.dg/flex-array-in-union-2.c
new file mode 100644
index ..130124bbe653
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/flex-array-in-union-2.c
@@ -0,0 +1,42 @@
+/* testing the correct usage of flexible array members in unions
+ and alone in structure: initialization */
+/* { dg-do run} */
+/* { dg-options "-O2" } */
+
+union with_fam_1 {
+ int a;
+ int b[];
+} with_fam_1_v = {.b = {1, 2, 3, 4}};
+
+union with_fam_2 {
+ int a;
+ char b[];
+} with_fam_2_v = {.a = 0x1f2f3f4f};
+
+union with_fam_3 {
+ char a[];
+ int b[];
+} with_fam_3_v = {.b = {0x1f2f3f4f, 0x5f6f7f7f}};
+
+struct only_fam {
+ int b[];
+} only_fam_v = {{7, 11}};
+
+int main ()
+{
+ if (with_fam_1_v.b[3] != 4
+ || with_fam_1_v.b[0] != 1)
+__builtin_abort ();
+ if (with_fam_2_v.b[3] != 0x1f
+ || with_fam_2_v.b[0] != 0x4f)
+__builtin_abort ();
+ if (with_fam_3_v.a[0] != 0x4f
+ || with_fam_3_v.a[7] != 0x5f)
+__builtin_abort ();
+ if (only_fam_v.b[0] != 7
+ || only_fam_v.b[1] != 11)
+__builtin_abort ();
+
+ return 0;
+}
+
--
2.31.1
