/* PR tree-optimization/90879 - fold zero-equality of strcmp between a longer string and a smaller array Test for a warning for strcmp of a longer string against smaller array. { dg-do compile } { dg-options "-O2 -Wall -Wstring-compare -Wno-stringop-truncation -ftrack-macro-expansion=0" } */ typedef __SIZE_TYPE__ size_t; extern void* memcpy (void*, const void*, size_t); extern int strcmp (const char*, const char*); extern size_t strlen (const char*); extern char* strcpy (char*, const char*); extern char* strncpy (char*, const char*, size_t); extern int strncmp (const char*, const char*, size_t); void sink (int, ...); #define sink(...) sink (__LINE__, __VA_ARGS__) extern char a1[1], a2[2], a3[3], a4[4], a5[5], a6[6], a7[7], a8[8], a9[9]; #define T(a, b) sink (0 == strcmp (a, b)) void test_string_cst (void) { const char *s1 = "1", *s2 = "12"; T (s1, a1); // { dg-warning ".strcmp. of a string of length 1 and an array of size 1 evaluates to nonzero" } T (s1, a2); T (s1, a3); T (a1, s1); // { dg-warning ".strcmp. of a string of length 1 and an array of size 1 evaluates to nonzero" } T (a2, s1); T (a3, s1); T (s2, a1); // { dg-warning ".strcmp. of a string of length 2 and an array of size 1 evaluates to nonzero" } T (s2, a2); // { dg-warning ".strcmp. of a string of length 2 and an array of size 2 evaluates to nonzero" } T (s2, a3); T (a1, s2); // { dg-warning ".strcmp. of a string of length 2 and an array of size 1 evaluates to nonzero" } T (a2, s2); // { dg-warning ".strcmp. of a string of length 2 and an array of size 2 evaluates to nonzero" } T (a3, s2); } void test_string_cst_off_cst (void) { const char *s1 = "1", *s2 = "12", *s3 = "123", *s4 = "1234"; T (s1, a2 + 1); // { dg-warning ".strcmp. of a string of length 1 and an array of size 1 evaluates to nonzero" } T (a2 + 1, s1); // { dg-warning ".strcmp. of a string of length 1 and an array of size 1 evaluates to nonzero" } T (s3 + 1, a2); // { dg-warning ".strcmp. of a string of length 2 and an array of size 2 evaluates to nonzero" } T (s3 + 1, a3); T (s2, a4 + 1); T (s2, a4 + 2); // { dg-warning ".strcmp. of a string of length 2 and an array of size 2 evaluates to nonzero" } T (s4, a4 + 1); // { dg-warning ".strcmp. of a string of length 4 and an array of size 3 evaluates to nonzero" } T (s3, a5 + 1); } /* Use strncpy below rather than memcpy until PR 91183 is resolved. */ #undef T #define T(s, n, a) \ do { \ char arr[32]; \ sink (arr); \ strncpy (arr, s, n < 0 ? strlen (s) + 1: n); \ sink (0 == strcmp (arr, a)); \ } while (0) void test_string_exact_length (void) { const char *s1 = "1", *s2 = "12"; T (s1, -1, a1); // { dg-warning ".strcmp. of a string of length 1 and an array of size 1 evaluates to nonzero" } T (s1, -1, a2); T (s1, -1, a3); T (s2, -1, a1); // { dg-warning ".strcmp. of a string of length 2 and an array of size 1 evaluates to nonzero" } T (s2, -1, a2); // { dg-warning ".strcmp. of a string of length 2 and an array of size 2 evaluates to nonzero" } T (s2, -1, a3); } void test_string_min_length (void) { const char *s1 = "1", *s2 = "12"; T (s1, 1, a1); // { dg-warning ".strcmp. of a string of length 1 or more and an array of size 1 evaluates to nonzero" } T (s1, 1, a2); T (s1, 1, a3); T (s2, 2, a1); // { dg-warning ".strcmp. of a string of length 2 or more and an array of size 1 evaluates to nonzero" } T (s2, 2, a2); // { dg-warning ".strcmp. of a string of length 2 or more and an array of size 2 evaluates to nonzero" } T (s2, 2, a3); } int test_strncmp_str_lit_var (const char *s, long n) { if (strncmp (s, "123456", n) == 0) // { dg-bogus "\\\[-Wstring-compare" } return 1; return 0; } int test_strlen_strncmp_str_lit_var (const char *s, long n) { if (__builtin_strlen (s) < n) return -1; if (n == 6) if (strncmp (s, "123456", n) == 0) // { dg-bogus "\\\[-Wstring-compare" } return 1; return 0; }