Red Hat Bugzilla – Bug 511185
kernel: build with -fno-delete-null-pointer-checks [rhel-3]
Last modified: 2009-11-03 17:00:26 EST
+++ This bug was initially created as a clone of Bug #511181 +++ Description of problem: http://gcc.gnu.org/onlinedocs/gcc-3.2.3/gcc/Optimize-Options.html -fdelete-null-pointer-checks Use global dataflow analysis to identify and eliminate useless checks for null pointers. The compiler assumes that dereferencing a null pointer would have halted the program. If a pointer is checked after it has already been dereferenced, it cannot be null. In some environments, this assumption is not true, and programs can safely dereference null pointers. Use -fno-delete-null-pointer-checks to disable this optimization for programs which depend on that behavior. Enabled at levels -O2, -O3, -Os.
Upstream commit: http://git.kernel.org/linus/a3ca86aea507904148870946d599e07a340b39bf
Upstream 2.4 commit: http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.4.37.y.git;a=commit;h=c23e12166a48df3c8a36a8263f37f5da8928e6b5
A patch for this issue has been included in build 2.4.21-61.EL.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2009-1550.html