[Possibly bug] Failed to compile on GCC 8.3.0

[runlevel5]

OS: Debian 8.3.0 GCC: gcc (Debian 8.3.0-6) 8.3.0 OpenAL source code: master branch at commit 9ecf3d076c1dd184760a6a40bb6a349db0f09f12

Compile option:

set(LIBTYPE STATIC)
option(FORCE_STATIC_VCRT "" ON)
option(ALSOFT_UTILS "" OFF)
option(ALSOFT_EXAMPLES "" OFF)
option(ALSOFT_UPDATE_BUILD_VERSION "" OFF)
option(ALSOFT_INSTALL "" OFF)
option(ALSOFT_INSTALL_CONFIG "" OFF)
option(ALSOFT_INSTALL_HRTF_DATA "" OFF)
option(ALSOFT_INSTALL_AMBDEC_PRESETS "" OFF)
option(ALSOFT_INSTALL_EXAMPLES "" OFF)
option(ALSOFT_INSTALL_UTILS "" OFF)

I ran into following errors:

[ 42%] Building C object extern/curl/lib/CMakeFiles/libcurl_static.dir/request.c.o

In file included from /__w/Q2RTX/Q2RTX/extern/openal-soft/common/ringbuffer.h:12,
                 from /__w/Q2RTX/Q2RTX/extern/openal-soft/common/ringbuffer.cpp:23:
/__w/Q2RTX/Q2RTX/extern/openal-soft/common/flexarray.h: In instantiation of 'struct al::FlexArrayStorage<std::byte, 16, true>':
/__w/Q2RTX/Q2RTX/extern/openal-soft/common/flexarray.h:78:51:   required from 'struct al::FlexArray<std::byte, 16>'
/__w/Q2RTX/Q2RTX/extern/openal-soft/common/ringbuffer.h:36:34:   required from here
/__w/Q2RTX/Q2RTX/extern/openal-soft/common/flexarray.h:20:59: error: requested alignment is not an integer constant
 struct alignas(std::max(alignment, alignof(al::span<T>))) FlexArrayStorage : al::span<T> {
                                                           ^~~~~~~~~~~~~~~~
[ 42%] Building C object extern/curl/lib/CMakeFiles/libcurl_static.dir/rtsp.c.o
[ 42%] Building C object extern/curl/lib/CMakeFiles/libcurl_static.dir/select.c.o
cc1plus: warning: unrecognized command line option '-Wno-interference-size'
cc1plus: warning: unrecognized command line option '-Wno-c++20-attribute-extensions'
make[2]: *** [extern/openal-soft/CMakeFiles/OpenAL.dir/build.make:178: extern/openal-soft/CMakeFiles/OpenAL.dir/common/ringbuffer.cpp.o] Error 1

[runlevel5]

I reckon it might be related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94929

[runlevel5]

As you might have known, there are many games ported to the SteamOS which currently uses GCC 8.3.0 for its v2 runtime pack. Therefore IMHO it would be great if openal-soft could be backward-compatible with GCC 8. I am more than happy to contribute workaround patches.

[kcat]

That bug report suggests it was fixed in GCC 8. I guess SteamOS can't update to a fixed version of 8?

Though if the issue is with using std::max in alignas specifically, it shouldn't be too much of a problem to work around. If other fixes are needed, I'd be fine with accepting them as long as they're not too invasive.

[runlevel5]

That bug report suggests it was fixed in GCC 8. I guess SteamOS can't update to a fixed version of 8?

The SteamOS v2 SDK uses Debian Jessie of which GCC is still on 8.3.0. I don't think I could convince Debian to bump GCC on that old version.

Though if the issue is with using std::max in alignas specifically, it shouldn't be too much of a problem to work around. If other fixes are needed, I'd be fine with accepting them as long as they're not too invasive.

I will make a new Pull Request

[runlevel5]

On second thought I think devs should move to the SteamOS RT v3 instead, I am not a big fan of introducing extra codes to handle edge cases of legacy compilers