From 7e1c86817a884973b313fac162108524d3170f69 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Wed, 9 Apr 2025 15:49:13 +0200
Subject: [PATCH v1 2/2] Build macOS shared modules as dylib rather than bundle

Historically, bundles (ld -bundle) were the only file type that could
be dynamically loaded at run time on macOS (OS X at the time).  These
were distinct from dynamic libraries (ld -dynamiclib (although the man
page says -dylib, but that apparently doesn't work)) that you use at
build time (-lfoo).  Therefore, that platform had a strict distinction
between shared libraries and shared modules, unlike other platforms.
Over time, macOS gained the ability to dlopen dynamic libraries as
well, so this distinction is obsolete.  Also, it appears that the
bundle file type is obsolescent on other Apple platforms.  So, to
simplify this, change our shared library makefiles to build the
dynamic library file type for both uses.  (There are still some
distinctions between the two in the build system, such as where they
are installed and how the output files are named, but they are now
internally the same file type.)  Meson also has the same change
pending in its master branch, so this will eventually become
consistent.

Discussion: https://www.postgresql.org/message-id/170e7e57-fe43-4e7e-8566-a96fcdf23075%40eisentraut.org
---
 src/Makefile.shlib            | 5 +++--
 src/makefiles/Makefile.darwin | 8 +-------
 2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/src/Makefile.shlib b/src/Makefile.shlib
index fa81f6ffdd6..18fb4d6fa3f 100644
--- a/src/Makefile.shlib
+++ b/src/Makefile.shlib
@@ -107,17 +107,18 @@ override CPPFLAGS += -DSO_MAJOR_VERSION=$(SO_MAJOR_VERSION)
 endif
 
 ifeq ($(PORTNAME), darwin)
+  LINK.shared		= $(COMPILER) -dynamiclib
   ifdef soname
     # linkable library
     ifneq ($(SO_MAJOR_VERSION), 0)
       version_link	= -compatibility_version $(SO_MAJOR_VERSION) -current_version $(SO_MAJOR_VERSION).$(SO_MINOR_VERSION)
     endif
-    LINK.shared		= $(COMPILER) -dynamiclib -install_name '$(libdir)/lib$(NAME).$(SO_MAJOR_VERSION)$(DLSUFFIX)' $(version_link) $(exported_symbols_list)
+    LINK.shared		+= -install_name '$(libdir)/lib$(NAME).$(SO_MAJOR_VERSION)$(DLSUFFIX)' $(version_link) $(exported_symbols_list)
     shlib		= lib$(NAME).$(SO_MAJOR_VERSION)$(DLSUFFIX)
     shlib_major		= lib$(NAME).$(SO_MAJOR_VERSION)$(DLSUFFIX)
   else
     # loadable module
-    LINK.shared		= $(COMPILER) -bundle
+    LINK.shared		+= -Wl,-undefined,dynamic_lookup
   endif
   BUILD.exports		= $(AWK) '/^[^\#]/ {printf "_%s\n",$$1}' $< >$@
   exports_file		= $(SHLIB_EXPORTS:%.txt=%.list)
diff --git a/src/makefiles/Makefile.darwin b/src/makefiles/Makefile.darwin
index 7095f66e25c..ade07eadc02 100644
--- a/src/makefiles/Makefile.darwin
+++ b/src/makefiles/Makefile.darwin
@@ -1,12 +1,6 @@
 # env var name to use in place of LD_LIBRARY_PATH
 ld_library_path_var = DYLD_LIBRARY_PATH
 
-ifdef PGXS
-  BE_DLLLIBS = -bundle_loader $(bindir)/postgres
-else
-  BE_DLLLIBS = -bundle_loader $(top_builddir)/src/backend/postgres
-endif
-
 # Rule for building a shared library from a single .o file
 %$(DLSUFFIX): %.o
-	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -bundle $(BE_DLLLIBS) -o $@
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -dynamiclib -Wl,-undefined,dynamic_lookup -o $@
-- 
2.49.0