https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66230
Bug ID: 66230
Summary: Using optimizations causes program to segfault
Product: gcc
Version: 4.9.2
Status: UNCONFIRMED
Severity: major
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: gpnuma at centaurean dot com
Target Milestone: ---
Hello,
First I'd like to point out that the code producing this error compiles and
runs fine in gcc 4.8.4-1 for Linux and OS/X and Clang 3.5, 3.6 (Linux) and 6.1
(OS/X), but fails with gcc 4.9.2 when using -O3 on both Linux and OS/X (in
debug mode it works fine).
The platform used for all these tests was x86_64.
To reproduce : clone and build https://github.com/centaurean/density with gcc
4.9.2.
Then run the following command :
./benchmark -3 some_file
This will turn into a segfault.
When I add the line [printf("anything");] just before DENSITY_MEMCPY(... here :
https://github.com/centaurean/density/blob/master/src/kernel_lion_decode.c#L187,
the program runs again normally without any segfault... that's really super
strange.
The function that fails is called via an array of function pointers, but I
don't think that's the problem since it works with any other compiler.
