This makes "make check" work on Mac OS X. Without this patch, on Mac OS X a default "./configure; make; make check" fails with errors like:
dyld[65265]: Library not loaded: /usr/local/pgsql/lib/libpq.5.dylib
Referenced from: <59A2EAF9-6298-3112-BEDB-EA9A62A9DB53> /Users/evan.jones/postgresql-clean/tmp_install/usr/local/pgsql/bin/initdb
Reason: tried: '/usr/local/pgsql/lib/libpq.5.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/usr/local/pgsql/lib/libpq.5.dylib' (no such file), '/usr/local/pgsql/lib/libpq.5.dylib' (no such file), '/usr/local/lib/libpq.5.dylib' (no such file), '/usr/lib/libpq.5.dylib' (no such file, not in dyld cache)
The reason is that at some point, Mac OS X started removing the DYLD_LIBRARY_PATH environment variable for "untrusted" executables [1]: "Any dynamic linker (dyld) environment variables, such as DYLD_LIBRARY_PATH, are purged when launching protected processes."
One solution is to explicitly pass the DYLD_LIBRARY_PATH environment variable to to the sub-process shell scripts that are run by pg_regress. To do this, I created an extra_envvars global variable which is set to the empty string "", but on Mac OS X, is filled in with "DYLD_LIBRARY_PATH=%s", where the %s is the current environment variable. The "make check" Makefile sets this environment variable to the temporary install directory, so this fixes the above errors.
I tested this on Mac OS X and on Linux (Ubuntu 23.04).
Thanks!
Evan Jones