Modify cdylib suffix on macOS

Author: emmatyping

Makefile.pre.in

@@ -63,6 +63,7 @@ CARGO_TARGET_DIR=@CARGO_TARGET_DIR@
 CARGO_PROFILE=@CARGO_PROFILE@
 CARGO_TARGET=@CARGO_TARGET@
 CARGO_TARGET_LINKER_ENV=@CARGO_TARGET_LINKER_ENV@
+CARGO_DYLIB_SUFFIX=@CARGO_DYLIB_SUFFIX@
 RUST_STATICLIB_DEP=@RUST_STATICLIB_DEP@
 
 GNULD=		@GNULD@

Modules/makesetup

@@ -301,7 +301,7 @@ sed -e 's/[ 	]*#.*//' -e '/^[ 	]*$/d' |
 				# Shared build: build each Rust module as a cdylib (.so)
 				for mod in $mods
 				do
-					rust_shared="target/\$(if \$(CARGO_TARGET),\$(CARGO_TARGET)/\$(CARGO_TARGET_DIR),\$(CARGO_TARGET_DIR))/lib$mod\$(SHLIB_SUFFIX)"
+					rust_shared="target/\$(if \$(CARGO_TARGET),\$(CARGO_TARGET)/\$(CARGO_TARGET_DIR),\$(CARGO_TARGET_DIR))/lib$mod\$(CARGO_DYLIB_SUFFIX)"
 					file="$srcdir/$mod\$(EXT_SUFFIX)"
 					SHAREDMODS="$SHAREDMODS $file"
 					BUILT_SHARED="$BUILT_SHARED $mod"

configure

@@ -4371,11 +4371,19 @@ if test -n "$CARGO_TARGET"; then
 else
   CARGO_TARGET_LINKER_ENV=""
 fi
+dnl Cargo's cdylib crate type uses the platform's native shared library
+dnl extension, which differs from CPython's SHLIB_SUFFIX on macOS/iOS
+dnl (CPython uses .so, Cargo uses .dylib).
+case "$host" in
+  *-apple-*)  CARGO_DYLIB_SUFFIX=".dylib";;
+  *)          CARGO_DYLIB_SUFFIX="$SHLIB_SUFFIX";;
+esac
 AC_SUBST([CARGO_HOME])
 AC_SUBST([CARGO_TARGET_DIR])
 AC_SUBST([CARGO_PROFILE])
 AC_SUBST([CARGO_TARGET])
 AC_SUBST([CARGO_TARGET_LINKER_ENV])
+AC_SUBST([CARGO_DYLIB_SUFFIX])
 
 
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