m4: Disable -Wdisabled-optimization

After b4f7793ce2, qemuxml2xmltest has apparently become big enough
to trigger a compilation error when using --enable-test-coverage on
aarch64:

    CC       qemuxml2xmltest.o
  qemuxml2xmltest.c: In function 'mymain':
  qemuxml2xmltest.c:1216:1: error: const/copy propagation disabled: 4361 basic blocks and 99285 registers [-Werror=disabled-optimization]
   }
   ^
  qemuxml2xmltest.c:1216:1: error: PRE disabled: 4361 basic blocks and 99285 registers [-Werror=disabled-optimization]
  qemuxml2xmltest.c:1216:1: error: const/copy propagation disabled: 4361 basic blocks and 99285 registers [-Werror=disabled-optimization]
  qemuxml2xmltest.c:1216:1: error: const/copy propagation disabled: 4361 basic blocks and 99285 registers [-Werror=disabled-optimization]

However, as the GCC documentation states, this warning is not really
caused by issues in our code, so it makes sense to disable it.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
This commit is contained in:
Andrea Bolognani 2017-09-05 16:37:50 +02:00
parent d143837bd1
commit fbe315bdc8

View File

@ -64,6 +64,11 @@ AC_DEFUN([LIBVIRT_COMPILE_WARNINGS],[
# Several conditionals expand the same on both branches
# depending on the particular platform/architecture
dontwarn="$dontwarn -Wduplicated-branches"
# > This warning does not generally indicate that there is anything wrong
# > with your code; it merely indicates that GCC's optimizers are unable
# > to handle the code effectively.
# Source: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
dontwarn="$dontwarn -Wdisabled-optimization"
# gcc 4.2 treats attribute(format) as an implicit attribute(nonnull),
# which triggers spurious warnings for our usage