opaque types and ASSERT_EQ #153
Description
I'm facing the issue, that I have problems when I do NULL checks for opaque types:
#include "utest.h"
struct Foo;
UTEST(a, b) {
struct Foo *foo = NULL;
ASSERT_EQ(NULL, foo);
}
UTEST_MAIN();clang-17 works here, but if I compile with gcc-13 I get the following error:
In file included from t.c:1:
t.c: In function 'utest_run_a_b':
utest.h:678:36: error: invalid use of undefined type 'struct Foo'
678 | #define UTEST_AUTO(x) __typeof__(x + 0)
| ^
utest.h:754:5: note: in expansion of macro 'UTEST_AUTO'
754 | UTEST_AUTO(y) yEval = (y); \
| ^~~~~~~~~~
utest.h:800:25: note: in expansion of macro 'UTEST_COND'
800 | #define ASSERT_EQ(x, y) UTEST_COND(x, y, ==, "", 1)
| ^~~~~~~~~~
t.c:7:9: note: in expansion of macro 'ASSERT_EQ'
7 | ASSERT_EQ(NULL, foo);
| ^~~~~~~~~
utest.h:643:41: error: arithmetic on pointer to an incomplete type
643 | : _Generic((val - val), ptrdiff_t \
| ^
utest.h:405:33: note: in definition of macro 'UTEST_PRINTF'
405 | fprintf(utest_state.output, __VA_ARGS__); \
| ^~~~~~~~~~~
utest.h:765:7: note: in expansion of macro 'utest_type_printer'
765 | utest_type_printer(yEval); \
| ^~~~~~~~~~~~~~~~~~
utest.h:800:25: note: in expansion of macro 'UTEST_COND'
800 | #define ASSERT_EQ(x, y) UTEST_COND(x, y, ==, "", 1)
| ^~~~~~~~~~
t.c:7:9: note: in expansion of macro 'ASSERT_EQ'
7 | ASSERT_EQ(NULL, foo);
| ^~~~~~~~~
utest.h:643:41: error: arithmetic on pointer to an incomplete type
643 | : _Generic((val - val), ptrdiff_t \
| ^
utest.h:407:10: note: in definition of macro 'UTEST_PRINTF'
407 | printf(__VA_ARGS__)
| ^~~~~~~~~~~
utest.h:765:7: note: in expansion of macro 'utest_type_printer'
765 | utest_type_printer(yEval); \
| ^~~~~~~~~~~~~~~~~~
utest.h:800:25: note: in expansion of macro 'UTEST_COND'
800 | #define ASSERT_EQ(x, y) UTEST_COND(x, y, ==, "", 1)
| ^~~~~~~~~~
t.c:7:9: note: in expansion of macro 'ASSERT_EQ'
7 | ASSERT_EQ(NULL, foo);
| ^~~~~~~~~
Out of curiousity: Why is typeof(x + 0) instead of typeof(x) used here? - It looks like some compiler quirk that you wanted to workaround