RemoteVstPlugin fails to build with with -flto

[plater]

I've disabled vst build in openSUSE meanwhile but maybe it's easy for someone familiar with lmms to find a fix. I've attached the entire build log. See:
https://build.opensuse.org/package/show/multimedia:apps/lmms to view the patches.
Build failure point:

Arbuthnot:/home/abuild/rpmbuild/BUILD/lmms-1.2.0/build/plugins/vst_base # cd /home/abuild/rpmbuild/BUILD/lmms-1.2.0/build/plugins/vst_base && /usr/bin/wineg++ -I/home/abuild/rpmbuild/BUILD/lmms-1.2.0/build -I/home/abuild/rpmbuild/BUILD/lmms-1.2.0/include -I/usr/include -I/usr/include/wine/windows -L/usr/lib64/libwine.so /home/abuild/rpmbuild/BUILD/lmms-1.2.0/plugins/vst_base/RemoteVstPlugin.cpp -std=c++0x -mwindows -lpthread -lole32 -m32 -nodefaultlibs /usr/lib/wine/libwinecrt0.a -L/usr/lib/wine/ -luser32 -lkernel32 -lgdi32 -fno-omit-frame-pointer -fno-exceptions -Wall -Werror=unused-function -Wno-sign-compare -Wno-strict-overflow -Wno-array-bounds -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables -fstack-clash-protection -Werror=return-type -flto=4 -DNDEBUG -fPIC -DPIC -pie -o ../RemoteVstPlugin
In file included from /usr/include/wine/windows/objbase.h:252,
                 from /usr/include/wine/windows/ole2.h:25,
                 from /usr/include/wine/windows/wtypes.h:13,
                 from /usr/include/wine/windows/winscard.h:22,
                 from /usr/include/wine/windows/windows.h:70,
                 from /home/abuild/rpmbuild/BUILD/lmms-1.2.0/plugins/vst_base/RemoteVstPlugin.cpp:64:
/usr/include/wine/windows/objidl.h:6100:15: error: ‘union _userSTGMEDIUM::<unnamed struct>::__WIDL_objidl_generated_name_0000000C’ invalid; an anonymous struct may only have public non-static data members [-fpermissive]
 6100 |         union __WIDL_objidl_generated_name_0000000C {
      |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
winegcc: g++ failed

rpmbuildlog.txt

[PhysSong]

It seems like it's a bug with Wine >= 4.14: https://bugs.winehq.org/show_bug.cgi?id=47710
According to doitsujin/dxvk#1182 (comment), -D__WIDL_objidl_generated_name_0000000C= is a possible workaround.

[plater]

With -D__WIDL_objidl_generated_name_0000000C="" included in the CXXFLAGS I get a link time error about an undefined ExitProcess due to the vst section choking on Link Time Optimization. This is a pity because everything else except vst builds with it. I've discovered that I can build the vst plugins without wine which is the best option for me, works with LTO as well.

[PhysSong]

I get a link time error about an undefined ExitProcess due to the vst section choking on Link Time Optimization.

That sounds like https://bugs.winehq.org/show_bug.cgi?id=41712

[plater]

I get a link time error about an undefined ExitProcess due to the vst section choking on Link Time Optimization.

That sounds like https://bugs.winehq.org/show_bug.cgi?id=41712

Can confirm it is.

[Reflexe]

I think we can close this issue? @PhysSong

[PhysSong]

The -flto part is still not fixed, but I'm not sure if it's worth fixing it.

[tank-trax]

try commenting out

/*__WIDL_objidl_generated_name_0000000C */

I had to do this to compile Carla

[plater]

I've revisited openSUSE's lmms build and the only build flag I have to remove is -m64 to allow the wine-32 build to succeed. grepping the build log finds 167 instances of -flto=auto so I don't understand the issue with lto. The only modification to the build is sed out -m64 and add -D__WIDL_objidl_generated_name_0000000C="" to the build flags.

[thmo]

The problem is still there on Fedora 34/i686, I think (for lmms 1.2.2):

# wineg++  ../../../plugins/vst_base/RemoteVstPlugin.cpp -I../../../include -I../../../i686-redhat-linux-gnu -lole32 -lpthread -std=c++0x -mwindows -O2 -m32 -flto=auto
/usr/bin/ld: /usr/bin/../lib/wine/libwinecrt0.a(exe_entry.o): warning: relocation against `strlen@@GLIBC_2.0' in read-only section `.text'
/usr/bin/ld: /usr/bin/../lib/wine/libwinecrt0.a(exe_entry.o): in function `__wine_spec_exe_entry':
(.text+0x19): undefined reference to `GetCommandLineA'
/usr/bin/ld: (.text+0x4c): undefined reference to `HeapAlloc'
/usr/bin/ld: (.text+0x107): undefined reference to `ExitProcess'
/usr/bin/ld: a.out.so: hidden symbol `HeapAlloc' isn't defined
/usr/bin/ld: final link failed: bad value
collect2: error: ld returned 1 exit status
winegcc: /usr/bin/g++ failed

with these wine packages installed:

# rpm -qa 'wine*'
wine-filesystem-6.7-1.fc34.noarch
wine-core-6.7-1.fc34.i686
wine-devel-6.7-1.fc34.i686

Compilation succeeds when omitting -flto=auto switch or adding -fno-lto (the warning is still there, but probably unrelated).

NB: Adding -D__WIDL_objidl_generated_name_0000000C="" does not fix the issue for me (which is to be expected, as this has been fixed in wine 5.0 already).

[luzpaz]

Is this issue impacted at all by #6672 (comment) ?

[Rossmaxx]

I'm closing this for now as we switched to use wine >= 6.0 and i persume the regression to not be there. If it arises again, feel free to reopen.