build: Adds C++ warning flag for C Variable-Length Arrays. #15342
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C VLAs are not supported in C++. However, the GNU compiler allows them as an extension, which it does not warn about when not in pedantic mode. Unfortunately, it's easy to accidentally write a VLA, even unintentionally-- adding this warning will help us catch that. Signed-off-by: Jesse Williamson <jwilliamson@suse.de>
liewegas
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@chardan next time, i'd recommend fix these warnings before enabling this |
wjwithagen
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Jun 4, 2017
- VLAs are in GCC and Clang, and are there to stay forever,
if only to be compatible with all the software that is already
out there.
- Theoretical debates about VLA being hard to implement are
long superceded by th actual implentations
- Before setting this flag is would be required to first start
work on fixing all the fallout/warnings that will arise from
setting -Wvla
- Allocating large variable/stuctures on the stack could be asking
for trouble, but changes that ceph tools are going to be running
on small embedded devices are rather slim.
Signed-off-by: Willem Jan Withagen <wjw@digiware.nl>
liewegas
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Jun 5, 2017
build: revert -Wvla from #15342 Reviewed-by: Kefu Chai <kchai@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com>
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C VLAs are not supported in C++. However, the GNU compiler allows
them as an extension, which it does not warn about when not in
pedantic mode. Unfortunately, it's easy to unintentionally write
a VLA-- adding this warning will help us catch that.
Signed-off-by: Jesse Williamson jwilliamson@suse.de