https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65709
Bug ID: 65709
Summary: [5 Regression] Bad code for LZ4 decompression with -O3
on x86_64
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: e...@coeus-group.com
Created attachment 35266
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35266&action=edit
Test data
With GCC 5 at -O3 on x86_64 some inputs to LZ4 will generate a segfault when
decompressing. This doesn't happen with GCC 4.9, or -O2. It does happen with
-O2 -ftree-loop-vectorize -fvect-cost-model=dynamic.
I have tested gcc-5.0.0-0.21.fc22.x86_64 from Fedora 22, as well as SVN
revision 221940.
To trigger the segfault pass the attached input (sum.lz4) as the only command
line argument to the preprocessed test case.
