From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.1) Gecko/20031114 Description of problem: The attached program is supposed to execute a for loop 262144 times, but when compiled with -O2, -O3, or -Os, the loop is executed only once. Version-Release number of selected component (if applicable): gcc-3.4.3-22.fc3 How reproducible: Always Steps to Reproduce: 1. Download the attached file for-loop-optimizing-bug.c 2. gcc -Wall -W -O2 -s for-loop-optimizing-bug.c -o for-loop-optimizing-bug 3. ./for-loop-optimizing-bug | wc -c Actual Results: 4096 Expected Results: 1073741824 Additional info: This FC3 system is using kernel version 2.6.11-1.27_FC3. Notice that this bug is not limited to i586, I have reproduced it on an i686 systems running FC2 and an athlon system running FC1.
Created attachment 115020 [details] Source that demonstrates the bug
Tracking upstream. gcc 3.2.3 fails the same way, gcc 4.0.0 is ok.