[Bug other/78678] New: possibly missing -Warray-bounds warning

[clyon at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78678

            Bug ID: 78678
           Summary: possibly missing -Warray-bounds warning
           Product: gcc
           Version: 7.0
               URL: https://bugs.linaro.org/show_bug.cgi?id=2349
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
          Assignee: unassigned at gcc dot gnu.org
          Reporter: clyon at gcc dot gnu.org
  Target Milestone: ---

Arnd reported bug https://bugs.linaro.org/show_bug.cgi?id=2349.

gcc -fsanitize=object-size shows a useful warning that is not seen without that
option.

Compiling the attached code results in a warning:
atyfb_base.c:167:33: warning: array subscript is above array bounds
[-Warray-bounds]
only if one uses -fsanitize=object-size.

Removing this flag also removes the warning, which could probably be generated.

I've checked with today's trunk on arm-linux-gnueabi.

To reproduce the problem, compile with:
$ arm-none-linux-gnueabi-gcc -Wall -O2 -fno-partial-inlining
-Wno-unused-but-set-variable -Wno-pointer-sign -fsanitize=object-size
atyfb_base.i -c
[generates warning]

recompile without -fsanitize=object-size, it does not generate any warning.