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__attribute__ ((externally_visible)) int global;
int func(void);
/* These must fail. */
int bad0(void) { return __builtin_constant_p(global); }
int bad1(void) { return __builtin_constant_p(global++); }
inline int bad2(int x) { return __builtin_constant_p(x++); }
inline int bad3(int x) { return __builtin_constant_p(x); }
inline int bad4(const char *x) { return __builtin_constant_p(x); }
int bad5(void) { return bad2(1); }
inline int bad6(int x) { return __builtin_constant_p(x+1); }
int bad7(void) { return __builtin_constant_p(func()); }
int bad8(void) { char buf[10]; return __builtin_constant_p(buf); }
int bad9(const char *x) { return __builtin_constant_p(x[123456]); }
int bad10(void) { return __builtin_constant_p(&global); }
/* These must pass, or we've broken gcc2 functionality. */
int good0(void) { return __builtin_constant_p(1); }
int good1(void) { return __builtin_constant_p("hi"); }
int good2(void) { return __builtin_constant_p((1234 + 45) & ~7); }
/* These are extensions to gcc2. Failure indicates an optimization
regression. */
int opt0(void) { return bad3(1); }
int opt1(void) { return bad6(1); }
int opt2(void) { return __builtin_constant_p("hi"[0]); }
/*
* Opt3 is known to fail. It is one of the important cases that glibc
* was interested in though, so keep this around as a reminder.
*
* The solution is to add bits to recover bytes from constant pool
* elements given nothing but a constant pool label and an offset.
* When we can do that, and we can simplify strlen after the fact,
* then we can enable recognition of constant pool labels as constants.
*/
/* int opt3(void) { return bad4("hi"); } */
/* Call through tables so -finline-functions can't screw with us. */
int (* volatile bad_t0[])(void) = {
bad0, bad1, bad5, bad7, bad8, bad10
};
int (* volatile bad_t1[])(int x) = {
bad2, bad3, bad6
};
int (* volatile bad_t2[])(const char *x) = {
bad4, bad9
};
int (* volatile good_t0[])(void) = {
good0, good1, good2
};
int (* volatile opt_t0[])(void) = {
opt0, opt1, opt2 /* , opt3 */
};
#define N(arr) (sizeof(arr)/sizeof(*arr))
int main()
{
int i;
for (i = 0; i < N(bad_t0); ++i)
if ((*bad_t0[i])())
abort();
for (i = 0; i < N(bad_t1); ++i)
if ((*bad_t1[i])(1))
abort();
for (i = 0; i < N(bad_t2); ++i)
if ((*bad_t2[i])("hi"))
abort();
for (i = 0; i < N(good_t0); ++i)
if (! (*good_t0[i])())
abort();
#ifdef __OPTIMIZE__
for (i = 0; i < N(opt_t0); ++i)
if (! (*opt_t0[i])())
abort();
#endif
exit(0);
}
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