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// This test program creates a very large number of unique histories.
// RUN: %clangxx_msan -fsanitize-memory-track-origins=2 -m64 -O3 %s -o %t
// RUN: MSAN_OPTIONS=origin_history_size=7 not %run %t >%t.out 2>&1
// RUN: FileCheck %s --check-prefix=CHECK7 < %t.out
// RUN: MSAN_OPTIONS=origin_history_size=2 not %run %t >%t.out 2>&1
// RUN: FileCheck %s --check-prefix=CHECK2 < %t.out
// RUN: MSAN_OPTIONS=origin_history_per_stack_limit=1 not %run %t >%t.out 2>&1
// RUN: FileCheck %s --check-prefix=CHECK-PER-STACK < %t.out
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static char *buf, *cur, *end;
void init() {
buf = new char[1000];
cur = buf;
end = buf + 1000;
}
void line_flush() {
char *p;
for (p = cur - 1; p >= buf; --p)
if (*p == '\n')
break;
if (p >= buf) {
size_t write_sz = p - buf + 1;
// write(2, buf, write_sz);
memmove(buf, p + 1, end - p - 1);
cur -= write_sz;
}
}
void buffered_write(const char *p, size_t sz) {
while (sz > 0) {
size_t copy_sz = end - cur;
if (sz < copy_sz) copy_sz = sz;
memcpy(cur, p, copy_sz);
cur += copy_sz;
sz -= copy_sz;
line_flush();
}
}
void fn1() {
buffered_write("a\n", 2);
}
void fn2() {
buffered_write("a\n", 2);
}
void fn3() {
buffered_write("a\n", 2);
}
int main(void) {
init();
for (int i = 0; i < 2000; ++i) {
fn1();
fn2();
fn3();
}
return buf[50];
}
// CHECK7: WARNING: MemorySanitizer: use-of-uninitialized-value
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was stored to memory at
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was stored to memory at
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was stored to memory at
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was stored to memory at
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was stored to memory at
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was stored to memory at
// CHECK7-NOT: Uninitialized value was stored to memory at
// CHECK7: Uninitialized value was created by a heap allocation
// CHECK2: WARNING: MemorySanitizer: use-of-uninitialized-value
// CHECK2-NOT: Uninitialized value was stored to memory at
// CHECK2: Uninitialized value was stored to memory at
// CHECK2-NOT: Uninitialized value was stored to memory at
// CHECK2: Uninitialized value was created by a heap allocation
// CHECK-PER-STACK: WARNING: MemorySanitizer: use-of-uninitialized-value
// CHECK-PER-STACK: Uninitialized value was stored to memory at
// CHECK-PER-STACK: in fn3
// CHECK-PER-STACK: Uninitialized value was stored to memory at
// CHECK-PER-STACK: in fn2
// CHECK-PER-STACK: Uninitialized value was stored to memory at
// CHECK-PER-STACK: in fn1
// CHECK-PER-STACK: Uninitialized value was created by a heap allocation
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