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[/] [openrisc/] [trunk/] [gnu-old/] [gcc-4.2.2/] [gcc/] [testsuite/] [gcc.dg/] [builtin-stringop-chk-2.c] - Rev 867
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/* This file was miscompiled by an earlier version of the object size checking patch. Object size in one of the memcpy calls was incorrectly determined to be 0 while it should be (size_t) -1 (== unknown). */ /* { dg-do compile } */ /* { dg-options "-O2" } */ #include "../gcc.c-torture/execute/builtins/chk.h" void *bar (int); extern void *malloc (__SIZE_TYPE__); struct A { int i, j, k; }; /* Here all object sizes are not known at compile time. There should be no warning, nor any checker functions called. */ void foo (const struct A *x, int y, const unsigned char *z) { unsigned int b; unsigned char *c = 0; b = (x->i & 0xff) == 1 ? 3 : 4; if (y) c = bar (x->j * x->k); const unsigned char *d = z; unsigned char *e = c; unsigned char *f = c + x->j * x->k; int g = 0; while (e < f) { unsigned int h = *d++; if (h & 128) { h = h - 128; g = e + h * b > f; if (g) h = (f - e) / b; if (b < 4) do { memcpy (e, d, 3); e += 3; } while (--h); else do { memcpy (e, d, 4); e += 4; } while (--h); d += b; } else { h *= b; g = e + h > f; if (g) h = f - e; memcpy (e, d, h); e += h; d += h; } } } /* The same routine, slightly modified: 1) c has known size at compile time 2) e += h was changed into e += 16. GCC could actually through VRP determine that in e += h is (h >= 0 && h <= 127), thus know it is pointer addition and not subtraction and know e's __builtin_object_size (e, 0) is at 512, but we are not there yet. */ unsigned char * baz (const struct A *x, const unsigned char *z) { unsigned int b; unsigned char *c = 0; b = (x->i & 0xff) == 1 ? 3 : 4; c = malloc (512); const unsigned char *d = z; unsigned char *e = c; unsigned char *f = c + x->j * x->k; int g = 0; while (e < f) { unsigned int h = *d++; if (h & 128) { h = h - 128; g = e + h * b > f; if (g) h = (f - e) / b; if (b < 4) do { memcpy (e, d, 3); e += 3; } while (--h); else do { memcpy (e, d, 513); /* { dg-warning "will always overflow" "memcpy" } */ e += 4; } while (--h); d += b; } else { h *= b; g = e + h > f; if (g) h = f - e; memcpy (e, d, h); /* e += h; */ e += 16; d += h; } } return c; }
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