[Bug 50996] New: GCC11 & wineg++ fatal error: stdlib.h: No such file

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=50996

Bug ID: 50996
           Summary: GCC11 & wineg++ fatal error: stdlib.h: No such file
           Product: Wine
           Version: 6.6
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 69835
  --> https://bugs.winehq.org/attachment.cgi?id=69835
Yabridge: add missing #include <optional>

Thank you for wine. On Fedora 34 with GCC11 I'm trying to build yabridge which
uses wineg++. Requires headers (glibc-devel, stdc++-devel, boost-devel, etc are
all installed)

Builds (not) with GCC11 (wine means wine+staging):

Wine 6.3 |  Wine 6.6
------------------------------------
Yabridge 3.0.2     Y [1]  |     N
Yabridge HEAD      Y [1]  |     N

[1] requires attached patch which adds a missing #include <optional> which was
not required with GCC10.

Error:

FAILED: libvst3_base_wine_64bit.a.p/subprojects_vst3_base_source_fbuffer.cpp.o 
wineg++ -Ilibvst3_base_wine_64bit.a.p -I. -I.. -I/usr/include
-fdiagnostics-color=always -pipe -D_FILE_OFFSET_BITS=64 -std=c++2a -O3 -fPIC
-isystem../subprojects/vst3 -isystemsubprojects/vst3 -DRELEASE=1 -DNOMINMAX
-DWINE_NOWINSOCK -m64 -Wno-cpp -MD -MQ
libvst3_base_wine_64bit.a.p/subprojects_vst3_base_source_fbuffer.cpp.o -MF
libvst3_base_wine_64bit.a.p/subprojects_vst3_base_source_fbuffer.cpp.o.d -o
libvst3_base_wine_64bit.a.p/subprojects_vst3_base_source_fbuffer.cpp.o -c
../subprojects/vst3/base/source/fbuffer.cpp
In file included from ../subprojects/vst3/base/source/fbuffer.cpp:40:
/usr/include/c++/11/cstdlib:75:15: fatal error: stdlib.h: No such file or
directory
   75 | #include_next <stdlib.h>
      |               ^~~~~~~~~~
compilation terminated.
winegcc: /usr/bin/g++ failed

My wine/gcc/c++ foo is limited but I'm happy to provide additional information
you require. Thanks.