Cog is not compiling using buildroot 2023.02.x

[WoeMat]

Hello again :).
Once again I'm trying to compile cog. I'm using the latest buildroot release 2023.02.x with the cog version 0.16.1.
I want to run cog on an 64bit Raspberry CM4.
During the build process I get this error message:

>>> cog 0.16.1 Building
PATH="/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/bin:/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/sbin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/lib/wsl/lib:/snap/bin:/usr/local/go/bin"  PYTHONNOUSERSITE=y /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/bin/ninja   -C /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/build/cog-0.16.1//build
ninja: Entering directory `/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/build/cog-0.16.1//build'
[52/60] Linking target launcher/cogctl
FAILED: launcher/cogctl
/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/bin/aarch64-buildroot-linux-gnu-gcc  -o launcher/cogctl launcher/cogctl.p/cogctl.c.o launcher/cogctl.p/.._core_cog-utils.c.o -Wl,--as-needed -Wl,--no-undefined -Wl,-O1 -Wl,--start-group /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot/usr/lib/libsoup-2.4.so -Wl,--export-dynamic /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot/usr/lib/libgmodule-2.0.so -pthread /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot/usr/lib/libglib-2.0.so /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot/usr/lib/libgio-2.0.so /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot/usr/lib/libgobject-2.0.so -Wl,--end-group
/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/lib/gcc/aarch64-buildroot-linux-gnu/11.3.0/../../../../aarch64-buildroot-linux-gnu/bin/ld: /home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/host/aarch64-buildroot-linux-gnu/sysroot/usr/lib64/libicuuc.so.70: undefined reference to `std::condition_variable::wait(std::unique_lock<std::mutex>&)@GLIBCXX_3.4.30'
collect2: error: ld returned 1 exit status
[53/60] Generating symbol file core/libcogcore.so.9.1.3.p/libcogcore.so.9.1.3.symbols
ninja: build stopped: subcommand failed.
package/pkg-generic.mk:290: recipe for target '/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/build/cog-0.16.1/.stamp_built' failed
make: *** [/home/woolf/projects/project001_Software/trunk/ControlPanelOS/buildroot/output/build/cog-0.16.1/.stamp_built] Error 1`

Any suggestions ?

[philn]

Seems like you should add -stdlib=libstdc++ to LDFLAGS? cc @aperezdc

[WoeMat]

But where? When I add thist argument to the cog.mk file in the cog packet folder in buildroot like this :
COG_LDFLAGS += -stdlib=libstdc++
I get this output

stderr: aarch64-buildroot-linux-gnu-gcc.br_real: error: unrecognized command-line option ‘-stdlib=libstdc++’

I'm building on an Ubuntu host system by the way.