cmake / clang on powerpc?

[Havard Eidnes <he%NetBSD.org@localhost>]

Hi,

I'm looking for some hints to find out why the build of clang 13
on NetBSD/powerpc 9.0 fals to add -lpthread or just -pthread to
the internal tools linking:

[  2%] Linking CXX executable ../../bin/clang-tblgen
ld: /usr/pkg/lib/libLLVMSupport.a(Threading.cpp.o):(.got2+0x44): undefined reference to `pthread_attr_init'
ld: /usr/pkg/lib/libLLVMSupport.a(Threading.cpp.o):(.got2+0x50): undefined reference to `pthread_attr_setstacksize'
ld: /usr/pkg/lib/libLLVMSupport.a(Threading.cpp.o):(.got2+0x58): undefined reference to `pthread_create'
ld: /usr/pkg/lib/libLLVMSupport.a(Threading.cpp.o):(.got2+0x60): undefined reference to `pthread_attr_destroy'
ld: /usr/pkg/lib/libLLVMSupport.a(Threading.cpp.o):(.got2+0x8c): undefined reference to `pthread_setname_np'
ld: /usr/pkg/lib/libLLVMSupport.a(Threading.cpp.o):(.got2+0x94): undefined reference to `pthread_getname_np'
ld: ld generated: undefined reference to `pthread_create'
*** Error code 1

Any hints to make cmake be more verbose about what it's doing,
and where that linker invocation comes from?

Regards,

- Håvard