TL:DR: Please disable building flang in devel/llvm16.
I was hoping to test the to Fortran compilers included in devel/llvm16. Unfortunately, neither flang16 nor flang-new16 are usable. % flang16 -o z a.f90 ld: error: undefined symbol: _FortranAioBeginExternalFormattedOutput >>> referenced by FIRModule >>> /mnt3/kargl/tmp/a-c99267.o:(_QQmain) >>> referenced by FIRModule >>> /mnt3/kargl/tmp/a-c99267.o:(_QQmain) >>> referenced by FIRModule >>> /mnt3/kargl/tmp/a-c99267.o:(_QQmain) >>> referenced 1 more times <snipped> % flang-new16 -o z a.f90 ld: error: undefined symbol: main >>> referenced by crt1_c.c:73 (/usr/src/lib/csu/amd64/crt1_c.c:73) >>> /usr/lib/crt1.o:(_start) ld: error: undefined symbol: _FortranAioBeginExternalFormattedOutput >>> referenced by FIRModule >>> /mnt3/kargl/tmp/a-9d28a3.o:(_QQmain) >>> referenced by FIRModule >>> /mnt3/kargl/tmp/a-9d28a3.o:(_QQmain) >>> referenced by FIRModule >>> /mnt3/kargl/tmp/a-9d28a3.o:(_QQmain) <snipped> So support libraries appear to be missing during the link stage, and looking at the verbose output shows that none of the libraries are actually given to the linker. To compound the matter, the libraries are static. There are no shared libraries. % find /usr/local/llvm16 -name \*Fortran\* | grep "\.a" /usr/local/llvm16/lib/libFortranCommon.a /usr/local/llvm16/lib/libFortranDecimal.a /usr/local/llvm16/lib/libFortranEvaluate.a /usr/local/llvm16/lib/libFortranLower.a /usr/local/llvm16/lib/libFortranParser.a /usr/local/llvm16/lib/libFortranRuntime.a /usr/local/llvm16/lib/libFortranSemantics.a /usr/local/llvm16/lib/libFortran_main.a % find /usr/local/llvm16 -name \*flang\* | grep "\.a" /usr/local/llvm16/lib/libflangFrontend.a /usr/local/llvm16/lib/libflangFrontendTool.a So building devel/llvm16 is a waste of cpu cycles and threshes memory. -- Steve