unix: remove makefile rules for building shared extension modules

We want to teach the build to produce a shared library. But we want
to statically link extension modules in libpython. We need to patch
makesetup so it doesn't produce rules to build shared extension
modules, as these would complicate the linking story.

Author: indygreg

cpython-unix/build-cpython.sh

@@ -30,6 +30,31 @@ cat Makefile.extra
 
 pushd Python-${PYTHON_VERSION}
 
+# We build all extensions statically. So remove the auto-generated make
+# rules that produce shared libraries for them.
+patch -p1 << "EOF"
+diff --git a/Modules/makesetup b/Modules/makesetup
+--- a/Modules/makesetup
++++ b/Modules/makesetup
+@@ -241,16 +241,6 @@ sed -e 's/[ 	]*#.*//' -e '/^[ 	]*$/d' |
+ 		case $doconfig in
+ 		yes)	OBJS="$OBJS $objs";;
+ 		esac
+-		for mod in $mods
+-		do
+-			file="$srcdir/$mod\$(EXT_SUFFIX)"
+-			case $doconfig in
+-			no)	SHAREDMODS="$SHAREDMODS $file";;
+-			esac
+-			rule="$file: $objs"
+-			rule="$rule; \$(BLDSHARED) $objs $libs $ExtraLibs -o $file"
+-			echo "$rule" >>$rulesf
+-		done
+ 	done
+ 
+ 	case $SHAREDMODS in
+EOF
+
 # Code that runs at ctypes module import time does not work with
 # non-dynamic binaries. Patch Python to work around this.
 # See https://bugs.python.org/issue37060.