On 26/08/2020 15.11, Emmanuel Blot wrote: > Hi, > > I’ve noticed that since meson builds have been enabled, on macOS, the > build outcome with undefined symbols has changed: > > - prior to meson introduction (v5.1.0): > * referencing an undeclared symbol in source code led to a warning at > compile stage > * referencing an undeclared symbol at link stage led to a fatal build > error (as usually expected) > > - since meson introduction > * same behavior at compile stage > * however, the linker does silently generate an application - which > fails at launch since the symbol is undefined. > > Step to reproduce: > > from softmmu/main.c, replace for example call to qemu_init() with > qemu_init2(); > > - v5.1.0: > softmmu/main.c:48:5: warning: implicit declaration of function > 'qemu_init2' is invalid in C99 [-Wimplicit-function-declaration] > qemu_init2(argc, argv, envp); > LINK riscv64-softmmu/qemu-system-riscv64 > Undefined symbols for architecture x86_64: > "_qemu_init2", referenced from: > _qemu_main in main.o > ld: symbol(s) not found for architecture x86_64 > clang: error: linker command failed with exit code 1 (use -v to see > invocation) > make[1]: *** [qemu-system-riscv64] Error 1 > > - current master: > softmmu/main.c:49:5: warning: implicit declaration of function > 'qemu_init2' is invalid in C99 [-Wimplicit-function-declaration] > qemu_init2(argc, argv, envp); > ^ > 1 warning generated. > [3/3] Linking target qemu-system-riscv64 > > > riscv64-softmmu/qemu-system-riscv64 > dyld: lazy symbol binding failed: Symbol not found: _qemu_init2 > Referenced from: > /Users/eblot/Sources/Git/github.com/QEMU/upstream/build/riscv64-softmmu/qemu-system-riscv64 > > Expected in: flat namespace > > 'riscv64-softmmu/qemu-system-ris…' terminated by signal SIGABRT (Abort) > > > This new behavior is likely to come from the linker flag: > > -Wl,-undefined,dynamic_lookup > > I’m not sure whether it is a new feature or a bug, but if the former > stands true, is there a way to disable this feature?
Seems like this is added by meson itself (see meson/mesonbuild/linkers.py), not by our meson.build files ... Paolo, any idea why this happens? Thomas
