Ugly GCC -Wattributes warnings that cannot be suppressed using /included/ variant

[pabristow]

I am seeing dozens of warnings (that cannot be suppressed using -W-no-attributes) like this:

Build: Release_gcc810 in hello_boost_test_included (compiler: GNU GCC 8.1)

c++.exe -Wall -fexceptions -O2 -Wno-attributes -flto=thin -I..\..\..\boost -c I:\boost\libs\hello_boost\example\hello_boost_test_included.cpp -o obj\Release\boost\libs\hello_boost\example\hello_boost_test_included.o
g++.exe  -o bin\Release\hello_boost_test_included.exe obj\Release\boost\libs\hello_boost\example\hello_boost_test_included.o  -s  
I:/boost/boost/test/impl/framework.ipp: In function 'setup_loggers':
I:/boost/boost/test/impl/framework.ipp:1145:1: warning: visibility attribute not supported in this configuration; ignored [-Wattributes]
 }
 ^
lto1.exe: warning: visibility attribute not supported in this configuration; ignored [-Wattributes]
lto1.exe: warning: visibility attribute not supported in this configuration; ignored [-Wattributes]
...

I:/boost/boost/test/impl/unit_test_parameters.ipp: In function 'init':
I:/boost/boost/test/impl/unit_test_parameters.ipp:745:1: warning: visibility attribute not supported in this configuration; ignored [-Wattributes]
 }
 ^
I:/boost/boost/test/impl/results_reporter.ipp: In function 'set_stream':
I:/boost/boost/test/impl/results_reporter.ipp:113:1: warning: visibility attribute not supported in this configuration; ignored [-Wattributes]
 }
 ^
I:/boost/boost/test/impl/framework.ipp: In function 'test_unit_aborted':
I:/boost/boost/test/impl/framework.ipp:1757:1: warning: visibility attribute not supported in this configuration; ignored [-Wattributes]
 }
..

This seem to be specific to using mingw (and Codeblocks 17.12)

https://stackoverflow.com/questions/26025708/warning-visibility-attribute-ignored-symbol-visibility-c-gcc

sheds a little light on what might be causing these messages.

Full log of this simple test of Boost.Test available on request.

This is harmless but annoying.

[raffienficiaud]

Hi,

Sorry about those warnings (at some point I need to fix the Appveyor to get those as well). Which Boost Test variant (header/shared/static) are you using in this configuration?

[raffienficiaud]

Sorry I missed this information from the title of the issue.

[raffienficiaud]

We can try hard to silence the warning, but I remember from a past project that this does not work well, and it seems that this would hide the real issue.

In the included variant, the macro BOOST_TEST_DECL evaluates to BOOST_SYMBOL_VISIBLE which evaluates to __attribute__((__visibility__("default"))), unconditionally. This does not cause any issue in the platforms I am testing on, but apparently MINGW is more picky.

My understanding is that in the included variant, BOOST_TEST_DECL can just evaluate to nothing and this should be also valid in all platforms.

The branch topic/GH-235-gcc-attribute-warnings is a tentative fix, it would be nice if you can give a try.

[pabristow]

I:\boost\libs\test>git status
HEAD detached at origin/topic/GH-235-gcc-attribute-warnings
nothing to commit, working tree clean
and recompiled my very simple use of Boost.test included with NO errors.

Program: I:\boost\libs\hello_boost\example\hello_boost_test_included.cpp
BuildInfo:
Platform Win32, 64-bit.
Compiler GNU C++ version 8.1.0
STL GNU libstdc++ version 20180502
Boost version 1.71.0

Also builds OK with GCC 9.2.0

BuildInfo:
Platform Win32, 64-bit.
Compiler GNU C++ version 9.2.0
STL GNU libstdc++ version 20190812
Boost version 1.71.0

(__MINGW64__is defined with value 1.)

So your fix seems to do the trick for Codeblock 17.2 using GCC and mingw64 :-)

Many thanks.

[raffienficiaud]

Merged to master