Re: [libvirt] [PATCH] m4: Disable -Wdisabled-optimization

After b4f7793ce269, qemuxml2xmltest has apparently become big enough to trigger a compilation error 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(a)redhat.com&gt; --- m4/virt-compile-warnings.m4 | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/m4/virt-compile-warnings.m4 b/m4/virt-compile-warnings.m4 index e8f135126..f18a08a8f 100644 --- a/m4/virt-compile-warnings.m4 +++ b/m4/virt-compile-warnings.m4 @@ -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