diff options
Diffstat (limited to 'gcc/testsuite/gcc.dg/Wstring-compare.c')
| -rw-r--r-- | gcc/testsuite/gcc.dg/Wstring-compare.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/Wstring-compare.c b/gcc/testsuite/gcc.dg/Wstring-compare.c new file mode 100644 index 0000000..0ca492d --- /dev/null +++ b/gcc/testsuite/gcc.dg/Wstring-compare.c @@ -0,0 +1,181 @@ +/* PR tree-optimization/90879 - fold zero-equality of strcmp between + a longer string and a smaller array + { dg-do compile } + { dg-options "-O2 -Wall -Wextra -ftrack-macro-expansion=0" } */ + +#include "strlenopt.h" + +#define T(a, b) sink (0 == strcmp (a, b), a, b) + +void sink (int, ...); + +struct S { char a4[4], c; }; + +extern char a4[4]; +extern char a5[5]; +extern char b4[4]; + +/* Verify that comparison of string literals with arrays with unknown + content but size that prevents them from comparing equal is diagnosed. */ + +void strcmp_array_lit (void) +{ + if (strcmp (a4, "1234")) // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero" } + // { dg-bogus "in this expreession" "unwanted note" { target *-*-* } .-1 } + sink (0, a4); + + int cmp; + cmp = strcmp (a4, "1234"); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero" } + if (cmp) // { dg-message "in this expression" } + sink (0, a4); + + T (a4, "4321"); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero " } + T (a4, "12345"); // { dg-warning "length 5 and an array of size 4 " } + T (a4, "123456"); // { dg-warning "length 6 and an array of size 4 " } + T ("1234", a4); // { dg-warning "length 4 and an array of size 4 " } + T ("12345", a4); // { dg-warning "length 5 and an array of size 4 " } + T ("123456", a4); // { dg-warning "length 6 and an array of size 4 " } +} + + +void strcmp_array_pstr (void) +{ + const char *s4 = "1234"; + + { + if (strcmp (a4, s4)) // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero" } + // { dg-bogus "in this expreession" "unwanted note" { target *-*-* } .-1 } + sink (1, a4); + else + sink (0, a4); + } + + { + int c; + c = strcmp (a4, s4); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero" } + if (c) // { dg-message "in this expression" } + sink (1, a4); + else + sink (0, a4); + } + + const char *t4 = "4321"; + const char *s5 = "12345"; + const char *s6 = "123456"; + + T (a4, t4); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero " } + T (a4, s5); // { dg-warning "length 5 and an array of size 4 " } + T (a4, s6); // { dg-warning "length 6 and an array of size 4 " } + T (s4, a4); // { dg-warning "length 4 and an array of size 4 " } + T (s5, a4); // { dg-warning "length 5 and an array of size 4 " } + T (s6, a4); // { dg-warning "length 6 and an array of size 4 " } +} + + +void strcmp_array_cond_pstr (int i) +{ + const char *s4 = i ? "1234" : "4321"; + T (a4, s4); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero " } + T (a5, s4); +} + +void strcmp_array_copy (void) +{ + char s[8]; + + { + strcpy (s, "1234"); + if (strcmp (a4, s)) // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero" } + // { dg-bogus "in this expreession" "unwanted note" { target *-*-* } .-1 } + sink (1, a4); + else + sink (0, a4); + } + + { + strcpy (s, "1234"); + + int c; + c = strcmp (a4, s); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero" } + if (c) // { dg-message "in this expression" } + sink (1, a4); + else + sink (0, a4); + } + + strcpy (s, "4321"); + T (a4, s); // { dg-warning "'strcmp' of a string of length 4 and an array of size 4 evaluates to nonzero " } + strcpy (s, "12345"); + T (a4, s); // { dg-warning "length 5 and an array of size 4 " } + strcpy (s, "123456"); + T (a4, s); // { dg-warning "length 6 and an array of size 4 " } + strcpy (s, "4321"); + T (s, a4); // { dg-warning "length 4 and an array of size 4 " } + strcpy (s, "54321"); + T (s, a4); // { dg-warning "length 5 and an array of size 4 " } + strcpy (s, "654321"); + T (s, a4); // { dg-warning "length 6 and an array of size 4 " } +} + + +void strcmp_member_array_lit (const struct S *p) +{ + T (p->a4, "1234"); // { dg-warning "length 4 and an array of size 4 " } +} + + +#undef T +#define T(a, b, n) sink (0 == strncmp (a, b, n), a, b) + +void strncmp_array_lit (void) +{ + if (strncmp (a4, "12345", 5)) // { dg-warning "'strncmp' of a string of length 5, an array of size 4 and bound of 5 evaluates to nonzero" } + // { dg-bogus "in this expreession" "unwanted note" { target *-*-* } .-1 } + sink (0, a4); + + int cmp; + cmp = strncmp (a4, "54321", 5); // { dg-warning "'strncmp' of a string of length 5, an array of size 4 and bound of 5 evaluates to nonzero" } + if (cmp) // { dg-message "in this expression" } + sink (0, a4); + + // Verify no warning when the bound is the same as the array size. + T (a4, "4321", 4); + T (a4, "654321", 4); + + T (a4, "12345", 5); // { dg-warning "length 5, an array of size 4 and bound of 5 " } + T (a4, "123456", 6); // { dg-warning "length 6, an array of size 4 and bound of 6" } + + T ("1234", a4, 4); + T ("12345", a4, 4); + + T ("12345", a4, 5); // { dg-warning "length 5, an array of size 4 and bound of 5 " } + T ("123456", a4, 6); // { dg-warning "length 6, an array of size 4 and bound of 6 " } +} + + +void strncmp_strarray_copy (void) +{ + { + char a[] = "1234"; + char b[6]; + strcpy (b, "12345"); + if (strncmp (a, b, 5)) // { dg-warning "'strncmp' of strings of length 4 and 5 and bound of 5 evaluates to nonzero" } + // { dg-bogus "in this expreession" "unwanted note" { target *-*-* } .-1 } + sink (0, a, b); + } + + { + char a[] = "4321"; + char b[6]; + strcpy (b, "54321"); + int cmp; + cmp = strncmp (a, b, 5); // { dg-warning "'strncmp' of strings of length 4 and 5 and bound of 5 evaluates to nonzero" } + if (cmp) // { dg-message "in this expression" } + sink (0, a, b); + } + + strcpy (a4, "abc"); + T (a4, "54321", 5); // { dg-warning "'strncmp' of strings of length 3 and 5 and bound of 5 evaluates to nonzero " } +} + + |