On Tue, Jul 29, 2014 at 06:49:09PM -0700, Greg Kroah-Hartman wrote: > 3.15-stable review patch. If anyone has any objections, please let me know. IMNSHO this is a too big hammer approach. The bug happened on a single file only (right?), so if anything, IMHO it could be disabled for that single file only, and better do it only for compilers with the bug. If there are wrong code bugs with -O2 (we've fixed many in the past), you also don't turn off -O2 everywhere, similarly for -Os or any other options. Disabling it just in case the same bug happens elsewhere when it actually took 5 years before the bug caused miscompilation of something is too defensive. We had at least 15 other wrong-code bugfixes just in between 4.9.0 and 4.9.1. -fvar-tracking-assignments doesn't make a small difference in debug info, but significant for optimized code. If you build the kernel without and with -fno-var-tracking-assignments, you can use e.g. the dwlocstat tool to see what kind of difference it makes for the kernel in particular in variable debug info coverage. > > --- a/Makefile > +++ b/Makefile > @@ -669,6 +669,8 @@ KBUILD_CFLAGS += -fomit-frame-pointer > endif > endif > > +KBUILD_CFLAGS += $(call cc-option, -fno-var-tracking-assignments) > + > ifdef CONFIG_DEBUG_INFO > KBUILD_CFLAGS += -g > KBUILD_AFLAGS += -Wa,--gdwarf-2 > Jakub -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html