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UpstandingHackers / hammer

Parser combinators for binary formats, in C. Yes, in C. What? Don't look at me like that.
GNU General Public License v2.0
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macOS build failure (and fix) #191

Closed c-alpha closed 4 years ago

c-alpha commented 5 years ago

On macOS, using the clang bundled with Xcode, the build fails:

clang -o build/opt/src/backends/regex.os -c -std=gnu99 -Wall -Wextra -Werror -Wno-unused-parameter -Wno-attributes -Wno-unused-variable -O3 -fPIC build/opt/src/backends/regex.c
build/opt/src/backends/regex.c:229:32: error: unknown warning group '-Wclobbered', ignored [-Werror,-Wunknown-warning-option]
#pragma GCC diagnostic ignored "-Wclobbered"
                               ^
1 error generated.
scons: *** [build/opt/src/backends/regex.os] Error 1
scons: building terminated because of errors.

This is because we're using clang "in GCC mode" by specifying -std=gnu99, but of course it's not the real McCoy, and thus the #pragma makes clang barf.

The solution is to check whether the compiler is clang inside the #idef __GCC__. This may seem counter-intuitive, but actually is logical (and works). The change felt a bit slim for a PR, so I'm including a patch with this issue.

Wclobbered.patch.zip

pesco commented 4 years ago

I believe I independently fixed this with #192