[tsan] Unify the stack trace render format between TSan and ASan

[kubamracek]

Summary

I always found it weird that TSan print backtraces in a different line format than ASan. Would it make sense to unify them?

In particular, I care about having the actual PC addresses in the stack frames. This is useful for pointing to the exact instruction that caused a race.

[dvyukov]

%M gives you exact location. Raw PC value is frequently not useful due to ASLR and modules.
I afraid this can break things.

[kubamracek]

Okay, how about just adding the raw PC to the beginning of the line, just like ASan does?

Raw PC is useful when you're in the debugger. The address is valid in the live process and you can easily ask the debugger to tell you where the PC belongs, what instruction is it, get disassembly around. That doesn't work that well with module name + offset.

[dvyukov]

You can also export TSAN_OPTIONS=stack_trace_format=... in your bashrc as necessary. That's we have it as config option.

lib/tsan/rtl/tsan_flags.cc

SetCommonFlagsDefaults();
     if (SANITIZER_GO) {
       // Does not work as expected for Go: runtime handles SIGABRT and crashes.
       cf.abort_on_error = false;
       // Go does not have mutexes.
     } else {
       cf.detect_deadlocks = true;
     }
     cf.print_suppressions = false;
-    cf.stack_trace_format = "    #%n %f %S %M";
+    cf.stack_trace_format = "    #%n %p %f %S %M";
     cf.exitcode = 66;
     cf.intercept_tls_get_addr = true;
     OverrideCommonFlags(cf);
   }
 
   f->SetDefaults();
 
   FlagParser parser;