Undefined third-party library symbols when building dylib on MacOS

Code
1

The following command generates a Makefile on linux that properly builds a .so library:

# Shared library
add_library(mbauxShared
            SHARED
            mb_cheb.c mb_delaun.c mb_intersectgrid.c mb_readwritegrd.c 
            mb_surface.c mb_track.c mb_truecont.c mb_zgrid.c)

However the same command generates a Makefile on MacOS that results in many undefined symbol errors, for symbols defined in third-party libraries. What are the proper commands that prevent this problem?

2

What are the exact errors?

3

If your library requires external (third-part) libraries to link, there should probably be a target_link_libraries(mbauxShared ...) command somewhere to link the libraries in.

4

The issue - and what looks to be a good solution - is described here.

5

I use the following linker option on macOS when I know that the symbols will be satisfied at runtime:

-undefined dynamic_lookup

This makes it possible in my project to not link against a specific version of the Python dll, since it is the Python dll loading my library anyway.

This flag depends on whether or not you are using Linux style linking:

-flat_namespace

To make this macOS specific:

IF (APPLE)
SET_TARGET_PROPERTIES(devsim_py3 PROPERTIES LINK_FLAGS
"-undefined dynamic_lookup -flat_namespace")
ENDIF (APPLE)
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