This directory contains NaCl-fied versions of Valgrind (Memcheck) and
ThreadSanitizer tools.

To use them, build your program with custom flags:
 * add -g -O0 to compilation flags
 * add -Wl,-u,have_nacl_valgrind_interceptors -lvalgrind to linker flags

Run it by prepending either memcheck.sh or tsan.sh to sel_ldr command line:

memcheck.sh [tool_options] nacl-sel_ldr -Q [sel_ldr_options] file.nexe

ThreadSanitizer has two modes of execution. By default it looks for data races
in trusted code:

tsan.sh [tool_options] nacl-sel_ldr -Q [sel_ldr_options] file.nexe

With --nacl_untrusted tool option it looks for data races in untrusted code:

tsan.sh --nacl_untrusted [tool_options] nacl-sel_ldr -Q [sel_ldr_options] file.nexe

Note that both Memcheck and ThreadSanitizer are only available for 64-bit Linux
system running an x86_64 NaCl binary.

More information about these tools can be found at:
 * http://valgrind.org/docs/manual/manual.html
 * http://code.google.com/p/data-race-test/wiki/ThreadSanitizer

Source code for the tools is available at:
 * http://code.google.com/p/valgrind-variant
 * http://code.google.com/p/data-race-test

---

A simple example.

 * Create 1.c with the following contents:

#include <stdio.h>
#include <stdlib.h>

int main(void) {
    int* arr = malloc(5 * sizeof(int));
    printf("%d\n", arr[5]);
    return 0;
}

 * Build it with the right options:

toolchain/linux_x86/bin/nacl64-gcc -o 1.nexe \
  -Wl,-u,have_nacl_valgrind_interceptors -m64 -O0 -g 1.c  -lvalgrind

 * Run:

memcheck.sh toolchain/linux_x86/bin/nacl64-sel_ldr -Q 1.nexe

 * Note Valgrind warnings among other output:

 Invalid read of size 4
    at 0xB0002030F: main 1.c:6
  Address 0xb0007234c is 0 bytes after a block of size 20 alloc'd
    at 0xB00022938: _malloc_r valgrind_interceptors.c:171
    by 0xB000202FF: main 1.c:5

 * Adding --leak-check=full to memcheck options, you will also get the following

 20 bytes in 1 blocks are definitely lost in loss record 9 of 50
    at 0xB00022938: _malloc_r valgrind_interceptors.c:171
    by 0xB000202FF: main 1.c:5
