/* PR middle-end/88232 - Please implement -Winfinite-recursion Verify simple cases without optimization. { dg-do compile } { dg-options "-Wall -Winfinite-recursion" } */ #define NORETURN __attribute__ ((noreturn)) typedef __SIZE_TYPE__ size_t; extern void abort (void); extern void exit (int); extern int ei; int (*pfi_v)(void); /* Make sure the warning doesn't assume every call has a DECL. */ int nowarn_pfi_v (void) { return pfi_v (); } int warn_fi_v (void) // { dg-warning "-Winfinite-recursion" } { return warn_fi_v (); // { dg-message "recursive call" } } /* Verify #pragma suppression works. */ #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Winfinite-recursion" int suppress_warn_fi_v (void) { return warn_fi_v (); } #pragma GCC diagnostic pop int nowarn_fi_v (void) { if (ei++ == 0) return nowarn_fi_v (); return 0; } int warn_if_i (int i) // { dg-warning "-Winfinite-recursion" } { if (i > 0) return warn_if_i (--i); // { dg-message "recursive call" } else if (i < 0) return warn_if_i (-i); // { dg-message "recursive call" } else return warn_if_i (7); // { dg-message "recursive call" } } int nowarn_if_i (int i) { if (i > 0) return nowarn_if_i (--i); else if (i < 0) return nowarn_if_i (-i); else return -1; } int nowarn_switch (int i, int a[]) { switch (i) { case 0: return nowarn_switch (a[3], a + 1); case 1: return nowarn_switch (a[5], a + 2); case 2: return nowarn_switch (a[7], a + 3); case 3: return nowarn_switch (a[9], a + 4); } return 77; } int warn_switch (int i, int a[]) // { dg-warning "-Winfinite-recursion" } { switch (i) { case 0: return warn_switch (a[3], a + 1); case 1: return warn_switch (a[5], a + 2); case 2: return warn_switch (a[7], a + 3); case 3: return warn_switch (a[9], a + 4); default: return warn_switch (a[1], a + 5); } } NORETURN void fnoreturn (void); /* Verify there's no warning for a function that doesn't return. */ int nowarn_call_noret (void) { fnoreturn (); } int warn_call_noret_r (void) // { dg-warning "-Winfinite-recursion" } { warn_call_noret_r (); // { dg-message "recursive call" } fnoreturn (); } /* Verify a warning even though the abort() call would prevent the infinite recursion. There's no good way to tell the two cases apart and letting a simple abort prevent the warning would make it ineffective in cases where it's the result of assert() expansion and not meant to actually prevent recursion. */ int warn_noret_call_abort_r (char *s, int n) // { dg-warning "-Winfinite-recursion" } { if (!s) abort (); if (n > 7) abort (); return n + warn_noret_call_abort_r (s, n - 1); // { dg-message "recursive call" } } /* Verify that a warning is not issued for an apparently infinitely recursive function like the one above where the recursion would be prevented by a call to a noreturn function if the recursive function is itself declared noreturn. */ NORETURN void nowarn_noret_call_abort_r (int n) { if (n > 7) abort (); nowarn_noret_call_abort_r (n - 1); } int warn_call_abort_r (int n) // { dg-warning "-Winfinite-recursion" } { n += warn_call_abort_r (n - 1); // { dg-message "recursive call" } if (n > 7) // unreachable abort (); return n; } /* And again with exit() for good measure. */ int warn_call_exit_r (int n) // { dg-warning "-Winfinite-recursion" } { n += warn_call_exit_r (n - 1); // { dg-message "recursive call" } if (n > 7) exit (0); return n; } struct __jmp_buf_tag { }; typedef struct __jmp_buf_tag jmp_buf[1]; extern jmp_buf jmpbuf; /* A call to longjmp() breaks infinite recursion. Verify it suppresses the warning. */ int nowarn_call_longjmp_r (int n) { if (n > 7) __builtin_longjmp (jmpbuf, 1); return n + nowarn_call_longjmp_r (n - 1); } int warn_call_longjmp_r (int n) // { dg-warning "-Winfinite-recursion" } { n += warn_call_longjmp_r (n - 1); // { dg-message "recursive call" } if (n > 7) __builtin_longjmp (jmpbuf, 1); return n; } struct __sigjmp_buf_tag { }; typedef struct __sigjmp_buf_tag sigjmp_buf[1]; extern sigjmp_buf sigjmpbuf; /* GCC has no __builtin_siglongjmp(). */ extern void siglongjmp (sigjmp_buf, int); /* A call to longjmp() breaks infinite recursion. Verify it suppresses the warning. */ int nowarn_call_siglongjmp_r (int n) { if (n > 7) siglongjmp (sigjmpbuf, 1); return n + nowarn_call_siglongjmp_r (n - 1); } int nowarn_while_do_call_r (int n) { int z = 0; while (n) z += nowarn_while_do_call_r (n--); return z; } int warn_do_while_call_r (int n) // { dg-warning "-Winfinite-recursion" } { int z = 0; do z += warn_do_while_call_r (n); // { dg-message "recursive call" } while (--n); return z; } /* Verify warnings for a naive replacement of a built-in fucntion. */ void* malloc (size_t n) // { dg-warning "-Winfinite-recursion" } { size_t *p = (size_t*)__builtin_malloc (n + sizeof n); // { dg-message "recursive call" } *p = n; return p + 1; }