libatomic support

[juvinious]

Hello,

Is it possible to get libatomic.a support for the gcc port?

Simple test to demonstrate:

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#include <atomic>
int main(){
        std::atomic<int> test;
        return 0;
}

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/opt/devkitpro/devkitPPC/bin/powerpc-eabi-g++ main.cpp -std=c++11 -o main -latomic
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: cannot find -latomic: No such file or directory
collect2: error: ld returned 1 exit status

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root@c5b726e60829:/opt# find -L /opt -name 'libatomic.a' 
root@c5b726e60829:/opt# find -L /usr/ -name 'libatomic.a' 
/usr/lib/gcc/x86_64-linux-gnu/10/libatomic.a

Any help would be much appreciated.

Thanks.

[WinterMute]

You don't need to add -latomic to use atomics.

[juvinious]

Ok I see, yeah it seems to work with some caveats.
I think the issue is with my inclusion of uint64_t types and additional libs.

Without including any of the libs I need it seems to be fine. When I add the libraries I need to link with it has undefined references to __atomic_*_8.
Now that I know a little more, I guess I can play around with it and see which library is causing the problem. I'll follow back up.

Test code:

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#include <atomic>

int main()
{
        std::atomic<uint64_t> test;
        std::atomic<bool> test2;
        test.store(3);
        test+= 2;
        test-=1;
        if (test != 1){
        }
        test2 = false;
        test2.store(true);
        int value = test.load();
        bool value2 = test.load();

        // Not defined / deleted
        //std::atomic<uint64_t> test3 = test;

        return 0;
}

No libraries compiles fine:

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root@4f0d20892574:/build# /opt/devkitpro/devkitPPC/bin/powerpc-eabi-g++ main.cpp -std=c++11 -mrvl -mcpu=750 -meabi -mhard-float -ffunction-sections -fdata-sections -O2 -o main 
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: warning: cannot find entry symbol _start; defaulting to 80004024
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: main: warning: allocated section `.data' not in segment

With needed libraries missing symbols:

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/opt/devkitpro/devkitPPC/bin/powerpc-eabi-g++ main.cpp -o main -L/opt/devkitpro/wut/lib -L/opt/devkitpro/portlibs/gamecube/lib -L/opt/devkitpro/portlibs/ppc/lib -Wl,--as-needed -Wl,--no-undefined -static -static-libgcc -static-libstdc++ -Wl,--start-group /opt/devkitpro/portlibs/ppc/lib/libharfbuzz.a -lm /opt/devkitpro/portlibs/ppc/lib/libfreetype.a /opt/devkitpro/portlibs/ppc/lib/libbz2.a /opt/devkitpro/portlibs/ppc/lib/libpng16.a /opt/devkitpro/portlibs/ppc/lib/libz.a /opt/devkitpro/portlibs/ppc/lib/libjpeg.a /opt/devkitpro/portlibs/gamecube/lib/libSDL2main.a /opt/devkitpro/portlibs/gamecube/lib/libSDL2.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/libogc/lib/cube/libaesnd.a /opt/devkitpro/libogc/lib/cube/libfat.a /opt/devkitpro/libogc/lib/cube/libogc.a /opt/devkitpro/portlibs/gamecube/lib/libSDL2_ttf.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/portlibs/gamecube/lib/libSDL2_mixer.a /opt/devkitpro/portlibs/ppc/lib/libvorbisidec.a /opt/devkitpro/portlibs/ppc/lib/libmodplug.a /opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/lib/libstdc++.a /opt/devkitpro/portlibs/ppc/lib/libmpg123.a /opt/devkitpro/portlibs/ppc/lib/libopusfile.a /opt/devkitpro/portlibs/ppc/lib/libopus.a /opt/devkitpro/portlibs/ppc/lib/libFLAC.a /opt/devkitpro/portlibs/ppc/lib/libogg.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/portlibs/gamecube/lib/libSDL2_gfx.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/portlibs/ppc/lib/libvorbis.a /opt/devkitpro/portlibs/ppc/lib/libvorbisfile.a -Wl,--end-group -mogc -mcpu=750 -meabi -mhard-float -mogc -mcpu=750 -meabi -mhard-float -mogc -mcpu=750 -meabi -mhard-float -mogc -mcpu=750 -meabi -mhard-float -mogc -DGEKKO -mcpu=750 -meabi -mhard-float
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: /tmp/ccVXHedv.o: in function `main':
main.cpp:(.text.main+0x94): undefined reference to `__atomic_store_8'
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: main.cpp:(.text.main+0x150): undefined reference to `__atomic_load_8'
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: main.cpp:(.text.main+0x1b0): undefined reference to `__atomic_load_8'
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: /tmp/ccVXHedv.o: in function `_ZNSt13__atomic_baseIyEpLEy':
main.cpp:(.text._ZNSt13__atomic_baseIyEpLEy[_ZNSt13__atomic_baseIyEpLEy]+0x3c): undefined reference to `__atomic_fetch_add_8'
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: /tmp/ccVXHedv.o: in function `_ZNSt13__atomic_baseIyEmIEy':
main.cpp:(.text._ZNSt13__atomic_baseIyEmIEy[_ZNSt13__atomic_baseIyEmIEy]+0x3c): undefined reference to `__atomic_fetch_sub_8'
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: /tmp/ccVXHedv.o: in function `_ZNKSt13__atomic_baseIyEcvyEv':
main.cpp:(.text._ZNKSt13__atomic_baseIyEcvyEv[_ZNKSt13__atomic_baseIyEcvyEv]+0x6c): undefined reference to `__atomic_load_8'
collect2: error: ld returned 1 exit status

[juvinious]

Found the culprit, when building against libogc. I removed it and now it's happy.

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root@4f0d20892574:/build# /opt/devkitpro/devkitPPC/bin/powerpc-eabi-g++ main.cpp -o main -L/opt/devkitpro/wut/lib -L/opt/devkitpro/portlibs/gamecube/lib -L/opt/devkitpro/portlibs/ppc/lib -Wl,--as-needed -Wl,--no-undefined -static -static-libgcc -static-libstdc++ -Wl,--start-group /opt/devkitpro/portlibs/ppc/lib/libharfbuzz.a -lm /opt/devkitpro/portlibs/ppc/lib/libfreetype.a /opt/devkitpro/portlibs/ppc/lib/libbz2.a /opt/devkitpro/portlibs/ppc/lib/libpng16.a /opt/devkitpro/portlibs/ppc/lib/libz.a /opt/devkitpro/portlibs/ppc/lib/libjpeg.a /opt/devkitpro/portlibs/gamecube/lib/libSDL2main.a /opt/devkitpro/portlibs/gamecube/lib/libSDL2.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/libogc/lib/cube/libaesnd.a /opt/devkitpro/libogc/lib/cube/libfat.a /opt/devkitpro/portlibs/gamecube/lib/libSDL2_ttf.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/portlibs/gamecube/lib/libSDL2_mixer.a /opt/devkitpro/portlibs/ppc/lib/libvorbisidec.a /opt/devkitpro/portlibs/ppc/lib/libmodplug.a /opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/lib/libstdc++.a /opt/devkitpro/portlibs/ppc/lib/libmpg123.a /opt/devkitpro/portlibs/ppc/lib/libopusfile.a /opt/devkitpro/portlibs/ppc/lib/libopus.a /opt/devkitpro/portlibs/ppc/lib/libFLAC.a /opt/devkitpro/portlibs/ppc/lib/libogg.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/portlibs/gamecube/lib/libSDL2_gfx.a -mogc -mcpu=750 -meabi -mhard-float /opt/devkitpro/portlibs/ppc/lib/libvorbis.a /opt/devkitpro/portlibs/ppc/lib/libvorbisfile.a -Wl,--end-group -mogc -mcpu=750 -meabi -mhard-float -mogc -mcpu=750 -meabi -mhard-float -mogc -mcpu=750 -meabi -mhard-float -mogc -mcpu=750 -meabi -mhard-float -mogc -DGEKKO -mcpu=750 -meabi -mhard-float
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: warning: cannot find entry symbol _start; defaulting to 80003124
root@4f0d20892574:/build# 

[juvinious]

Ok I might have jumped the gun on that one, it might be related to order and all the included flags. Let me continue to test I'll eventually figure it out.
Thanks for your help, much appreciated!

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root@4f0d20892574:/build# /opt/devkitpro/devkitPPC/bin/powerpc-eabi-g++ main.cpp -std=c++11 -mrvl -mcpu=750 -meabi -mhard-float -ffunction-sections -fdata-sections -O2 -o main  -L/opt/devkitpro/libogc/lib/cube/libogc.a
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: warning: cannot find entry symbol _start; defaulting to 80004024
/opt/devkitpro/devkitPPC/bin/../lib/gcc/powerpc-eabi/13.2.0/../../../../powerpc-eabi/bin/ld: main: warning: allocated section `.data' not in segment
root@4f0d20892574:/build# 

[juvinious]

So I'm still kind of stuck. I threw the config into the template:

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#---------------------------------------------------------------------------------
# any extra libraries we wish to link with the project
#---------------------------------------------------------------------------------
LIBS    :=      -lharfbuzz -lm -lfreetype -lbz2 -lpng16 -lz -ljpeg -lSDL2main -lSDL2 -laesnd -lfat -logc -lm -lSDL2_ttf -lSDL2_mixer -lvorbisidec -lmodplug -lstdc++ -lmpg123 -lopusfile -lopus -lFLAC -logg -lSDL2_gfx -lvorbis -lvorbisfile

#---------------------------------------------------------------------------------
# list of directories containing libraries, this must be the top level containing
# include and lib
#---------------------------------------------------------------------------------
LIBDIRS :=      /opt/devkitpro/portlibs/ppc /opt/devkitpro/portlibs/gamecube /opt/devkitpro/libogc/lib/cube

[WinterMute]

So I'm still kind of stuck. I threw the config into the template:

OK. It seems that libatomic is needed for 64bit atomics on 32bit processors. I'm told this is probably going to be slow so it might be worth considering whether or not you really need this. It's not a request I've had before anyway so, afaik, it's not a common issue. I can look at enabling libatomic but that's never been tested so no guarantees.

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LIBS    :=      -lharfbuzz -lm -lfreetype -lbz2 -lpng16 -lz -ljpeg -lSDL2main -lSDL2 -laesnd -lfat -logc -lm -lSDL2_ttf -lSDL2_mixer -lvorbisidec -lmodplug -lstdc++ -lmpg123 -lopusfile -lopus -lFLAC -logg -lSDL2_gfx -lvorbis -lvorbisfile

This part can largely be replaced with this line I think which has the added bonus of dealing with link order. This is off the top of my head so I might be missing a lib. /opt/devkitpro/portlibs/gamecube/bin/powerpc-eabi-pkg-config --list-all will tell you what libs this will understand.

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LIBS    := `$(PREFIX)pkg-config --libs SDL2_gfx SDL2_mixer SDL2_ttf`

also add `$(PREFIX)pkg-config --cflags SDL2_gfx SDL2_mixer SDL2_ttf` to CFLAGS

[/code]
LIBDIRS := /opt/devkitpro/portlibs/ppc /opt/devkitpro/portlibs/gamecube /opt/devkitpro/libogc/lib/cube
[/code]

LIBDIRS can just be left blank or add $(PORTLIBS) although the pkg-config incantation should take care of the needed -L options.

[WinterMute]

libatomic configury currently says no

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configure: error: Configuration powerpc-unknown-eabi is unsupported.

There are some other dependencies we need to satisfy that aren't straightforward unfortunately. It's unlikely we'll get back to looking at this soon, sorry.

[juvinious]

libatomic configury currently says no

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configure: error: Configuration powerpc-unknown-eabi is unsupported.

There are some other dependencies we need to satisfy that aren't straightforward unfortunately. It's unlikely we'll get back to looking at this soon, sorry.

Ok no problem. I'll figure out a workaround for these targets.
I appreciate your help. Thanks.