Thomas Lockhart wrote:
>>>But I do override some parameters in my Makefile.custom:
>>>CFLAGS+= -g -O0 -DUSE_ASSERT_CHECKING
>>>
>>If you use -O0 then you miss most of the interesting warnings.
>>
>
>?? Not in this case. afaik -O0 suppresses most optimizations (and hence
>does not reorder instructions, which is why I use it for debugging; I
>know, debuggers nowadays work pretty well even with instruction
>reordering, but...).
>
>Anyway, compiling with "-O2" on variable.c still does not show the
>warnings with my 2.96.x compiler...
>
It's actually the optimiser that allows a large number of the warnings
to be uncovered. It generates extra code-path and coverage information,
as well as other things, that are needed for the guts of GCC to squawk
about a number of odd behaviours.