https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65367
Bug ID: 65367
Summary: indefinite loop occurs with sanitize enabled and
certain optimization options
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: mike at cchtml dot com
Created attachment 34997
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34997&action=edit
makedep.pp
When attempting to debug a gcc5/wine issue I ran across an infinite loop when
certain optimization flags are set. The "tools/makedep.c" program during wine's
autotools configure process is where the issue is occurring.
Compile the attached pre-processed code with the following:
gcc -x cpp-output ./makedep.pp -mtune=generic -march=x86-64 -O1
-fsanitize=undefined -fno-tree-ccp -fno-tree-copy-prop -fno-tree-dominator-opts
-fno-tree-fre -o makedep.o
The loop only occurs when -O1 is specified (doesn't happen with -O2+) and all
four tree optimizations are disabled simultaneously. If any are enabled it does
not loop. If sanitize is disabled it does not loop. GCC 4.9 compiles the code
without looping.
$ gcc --version
gcc (GCC) 5.0.0 20150226 (Red Hat 5.0.0-0.18)
