> On Apr 25, 2024, at 10:13, Siddhesh Poyarekar <siddh...@gotplt.org> wrote:
>
> On 2024-04-25 10:06, Qing Zhao wrote:
>> gcc/testsuite/ChangeLog:
>> * c-c++-common/fam-in-union-alone-in-struct-1.c: New testcase.
>> * c-c++-common/fam-in-union-alone-in-struct-2.c: New testcase.
>> * c-c++-common/fam-in-union-alone-in-struct-3.c: New testcase.
>> ---
>
> Sorry I should have commented sooner; could you please also add tests for
> __bos/__bdos for such unions and structs?
Yes, nice suggestion! Will do.
Thanks a lot.
Qing
>
> Thanks,
> Sid
>
>> .../fam-in-union-alone-in-struct-1.c | 52 +++++++++++++++++++
>> .../fam-in-union-alone-in-struct-2.c | 51 ++++++++++++++++++
>> .../fam-in-union-alone-in-struct-3.c | 36 +++++++++++++
>> 3 files changed, 139 insertions(+)
>> create mode 100644
>> gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-1.c
>> create mode 100644
>> gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-2.c
>> create mode 100644
>> gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-3.c
>> diff --git a/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-1.c
>> b/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-1.c
>> new file mode 100644
>> index 000000000000..7d4721aa95ac
>> --- /dev/null
>> +++ b/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-1.c
>> @@ -0,0 +1,52 @@
>> +/* testing the correct usage of flexible array members in unions
>> + and alone in structures. */
>> +/* { dg-do run} */
>> +/* { dg-options "-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" } */
>> + /* { dg-warning "in an otherwise empty" "" { target c++ } .-1 } */
>> + int b[]; /* { dg-warning "flexible array member in union is a GCC
>> extension" } */
>> +};
>> +
>> +struct only_fam {
>> + int b[];
>> + /* { dg-warning "in a struct with no named members" "" { target c } .-1 }
>> */
>> + /* { dg-warning "in an otherwise empty" "" { target c++ } .-2 } */
>> + /* { dg-warning "forbids flexible array member" "" { target c++ } .-3 } */
>> +};
>> +
>> +struct only_fam_2 {
>> + unsigned int : 2;
>> + unsigned int : 3;
>> + int b[];
>> + /* { dg-warning "in a struct with no named members" "" { target c } .-1 }
>> */
>> + /* { dg-warning "in an otherwise empty" "" { target c++ } .-2 } */
>> + /* { dg-warning "forbids flexible array member" "" { target c++ } .-3 } */
>> +};
>> +
>> +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 ();
>> + if (sizeof (struct only_fam_2) != sizeof (int))
>> + __builtin_abort ();
>> + return 0;
>> +}
>> +
>> diff --git a/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-2.c
>> b/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-2.c
>> new file mode 100644
>> index 000000000000..3743f9e7dac5
>> --- /dev/null
>> +++ b/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-2.c
>> @@ -0,0 +1,51 @@
>> +/* testing the correct usage of flexible array members in unions
>> + and alone in structures: 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}};
>> +
>> +struct only_fam_2 {
>> + unsigned int : 2;
>> + unsigned int : 3;
>> + int b[];
>> +} only_fam_2_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 ();
>> + if (only_fam_2_v.b[0] != 7
>> + || only_fam_2_v.b[1] != 11)
>> + __builtin_abort ();
>> +
>> + return 0;
>> +}
>> +
>> diff --git a/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-3.c
>> b/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-3.c
>> new file mode 100644
>> index 000000000000..dd36fa01306d
>> --- /dev/null
>> +++ b/gcc/testsuite/c-c++-common/fam-in-union-alone-in-struct-3.c
>> @@ -0,0 +1,36 @@
>> +/* testing the correct usage of flexible array members in unions
>> + and alone in structures. */
>> +/* { dg-do compile } */
>> +/* { dg-options "-pedantic-errors" } */
>> +
>> +union with_fam_1 {
>> + int a;
>> + int b[]; /* { dg-error "flexible array member in union is a GCC
>> extension" } */
>> +};
>> +
>> +union with_fam_2 {
>> + char a;
>> + int b[]; /* { dg-error "flexible array member in union is a GCC
>> extension" } */
>> +};
>> +
>> +union with_fam_3 {
>> + char a[]; /* { dg-error "flexible array member in union is a GCC
>> extension" } */
>> + /* { dg-error "in an otherwise empty" "" { target c++ } .-1 } */
>> + int b[]; /* { dg-error "flexible array member in union is a GCC
>> extension" } */
>> +};
>> +
>> +struct only_fam {
>> + int b[];
>> + /* { dg-error "in a struct with no named members" "" { target c } .-1 } */
>> + /* { dg-error "in an otherwise empty" "" { target c++ } .-2 } */
>> + /* { dg-error "forbids flexible array member" "" { target c++ } .-3 } */
>> +};
>> +
>> +struct only_fam_2 {
>> + unsigned int : 2;
>> + unsigned int : 3;
>> + int b[];
>> + /* { dg-error "in a struct with no named members" "" { target c } .-1 } */
>> + /* { dg-error "in an otherwise empty" "" { target c++ } .-2 } */
>> + /* { dg-error "forbids flexible array member" "" { target c++ } .-3 } */
>> +};