On Mon, Jun 29, 2026 at 01:23:41PM +0100, Lorenzo Stoakes wrote:
> -#define ASSERT_TRUE(_expr) \
> - do { \
> - if (!(_expr)) { \
> - fprintf(stderr, \
> - "Assert FAILED at %s:%d:%s(): %s is FALSE.\n", \
> - __FILE__, __LINE__, __FUNCTION__, #_expr); \
> - return false; \
> - } \
> +#define __ASSERT_TRUE(_expr, _fmt, ...)
> \
> + do { \
> + if (!(_expr)) { \
> + fprintf(stderr, \
> + "Assert FAILED at %s:%d:%s(): %s is FALSE" \
> + _fmt ".\n", \
> + __FILE__, __LINE__, __FUNCTION__, #_expr \
> + __VA_OPT__(,) __VA_ARGS__); \
> + return false; \
> + } \
> } while (0)
>
> +#define __TO_SCALAR(x) ((unsigned long long)(uintptr_t)(x))
> +
> +#define ASSERT_TRUE(_expr) __ASSERT_TRUE(_expr, "")
Mmmmm... macro madness.... I don't think this is what you want.
I think you end up double-running the expression in the failure branch.
ASSERT_EQ(cleanup_mm(&mm, &vmi), 2)
run through the preprocessor expands to:
do {
if (!( (cleanup_mm(&mm, &vmi)) == (2) )) {
**** first run ****
fprintf(stderr,
"Assert FAILED at %s:%d:%s(): %s is FALSE" " (0x%llx != 0x%llx)"
".\n",
"merge.c", 645, __FUNCTION__,
"(cleanup_mm(&mm, &vmi)) == (2)",
((unsigned long long)(uintptr_t)(cleanup_mm(&mm, &vmi))),
**** second run ****
((unsigned long long)(uintptr_t)(2)));
return false;
}
} while (0);
A bunch of existing ASSERT callers mutate state, so there's no guarantee
the printed value matches teh actual test value.
I think you want something like:
#define ASSERT_EQ(_val1, _val2) do { \
__auto_type _v1 = (_val1); \
__auto_type _v2 = (_val2); \
__ASSERT_TRUE(_v1 == _v2, " (0x%llx != 0x%llx)", \
__TO_SCALAR(_v1), __TO_SCALAR(_v2)); \
} while (0)
which expands to:
do {
__auto_type _v1 = (cleanup_mm(&mm, &vmi));
__auto_type _v2 = (2);
do {
if (!(_v1 == _v2)) {
fprintf(stderr, "...FALSE (0x%llx != 0x%llx).\n",
"merge.c", 645, __FUNCTION__, "_v1 == _v2",
((unsigned long long)(uintptr_t)(_v1)),
((unsigned long long)(uintptr_t)(_v2)));
return false;
}
} while (0);
} while (0);
~Gregory
