Red Hat Bugzilla – Bug 963485
bad code generation
Last modified: 2013-07-18 23:17:36 EDT
Created attachment 748520 [details] Bug testcase Description of problem: The attached code segfaults when compiled with g++ -fPIC -O3 and works at -O2. Version-Release number of selected component (if applicable): gcc version 4.4.7 20120313 (Red Hat 4.4.7-3) (GCC) How reproducible: g++ -fPIC -O3 bad.cc ./a.out Steps to Reproduce: 1. 2. 3. Actual results: segfault Expected results: terminate Additional info: gcc 4.7.2 compiles correctly at -O3
The testcase is bogus. First of all, if you run it without arguments, it will of course crash already inside of atoi. But if you pass it argument that is not a multiple of pointer size, then the array of pointers is necessary misaligned and the testcase doesn't try to adjust it for that case (usually programs first put the aggregates that need to be aligned and only after that what doesn't need special alignment, you do it the other way around).