| Message ID | 3ce0ef8c-3a2d-65c8-081b-48a4150ffb06@tachyum.com |
|---|---|
| State | New |
| Headers | show |
| Series | [committed] Fix argument to pthread_join | expand |
diff --git a/gcc/testsuite/g++.dg/gcov/gcov-threads-1.C b/gcc/testsuite/g++.dg/gcov/gcov-threads-1.C index b020dd87d4c..3ae00789439 100644 --- a/gcc/testsuite/g++.dg/gcov/gcov-threads-1.C +++ b/gcc/testsuite/g++.dg/gcov/gcov-threads-1.C @@ -36,7 +36,7 @@ int main(int argc, char **argv) { assert (r == 0); /* count(5*) */ } - int ret; + void *ret; for (int i = 0; i < NR; i++) { int r = pthread_join (t[i], (void**)&ret);
This showed up as a segfault running the gcov-threads-1.C test in qemu system mode on our internal port. We're passing the address of an int to pthread_join. That int object is only guaranteed 4 byte alignment. Later when pthread_join wants to store a pointer into that location, we naturally fault due to misalignment. This is also a stack overrun since the pointer is 64 bits, but we've only got 32 bits of stack space allocated. pthread_join really wants a pointer to a pointer. So instead of passing &int_var, we can just pass &pointer_var. That also avoids the silly cast. We never use the value anyway, so we could just as easily pass NULL. This may also be the root cause of the riscv64 gcov-threads-1 failure that you can find in the gcc-testresults archives. Bootstrapped and tested on x86, also verified that gcov-threads-1.C now works with our internal port. Committed to the trunk. Jeff commit 0853f392a213ef2cecc71ef5349aab079e30f5a0 Author: Jeff Law <jlaw@localhost.localdomain> Date: Tue Jul 27 14:14:05 2021 -0400 Fix argument to pthread_join gcc/testsuite * g++.dg/gcov/gcov-threads-1.C: Fix argument to pthread_join.