Fix -Wno-unknown-warning support detection
authorPedro Alves <palves@redhat.com>
Wed, 16 Dec 2015 22:56:48 +0000 (22:56 +0000)
committerPedro Alves <palves@redhat.com>
Wed, 16 Dec 2015 22:56:49 +0000 (22:56 +0000)
commit7544db951abbb5dca5373dcc7ae83ed60c0782ad
tree1d330718ad64483b8d7aea34ebc97152168d4b12
parenta4e22a5df64a46bc99f737a982c0b9d1e8a45e2b
Fix -Wno-unknown-warning support detection

Ref: https://sourceware.org/ml/gdb/2015-12/msg00024.html

We have code in configure.ac that tries to detect whether the compiler
supports each warning and suppress it if not, but that doesn't work
with "-Wno-" options, because gcc doesn't error out for
-Wno-unknown-warning unless other diagnostics are being produced.

See https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html.

Handle this by checking whether -Wfoo works when we actually want
-Wno-foo.

gdb/ChangeLog:
2015-12-16  Pedro Alves  <palves@redhat.com>

* configure.ac (compiler warning flags): When testing a
-Wno-foo option, check whether -Wfoo works instead.
* configure: Regenerate.

gdb/gdbserver/ChangeLog:
2015-12-16  Pedro Alves  <palves@redhat.com>

* configure.ac (compiler warning flags): When testing a
-Wno-foo option, check whether -Wfoo works instead.
* configure: Regenerate.
gdb/ChangeLog
gdb/configure
gdb/configure.ac
gdb/gdbserver/ChangeLog
gdb/gdbserver/configure
gdb/gdbserver/configure.ac