Issue python#18486: MINGW: dynamic loading support

Author: Roumen Petrov

Makefile.pre.in

@@ -807,6 +807,12 @@ Python/dynload_hpux.o: $(srcdir)/Python/dynload_hpux.c Makefile
 		-DSHLIB_EXT='"$(EXT_SUFFIX)"' \
 		-o $@ $(srcdir)/Python/dynload_hpux.c
 
+Python/dynload_win.o: $(srcdir)/Python/dynload_win.c Makefile
+	$(CC) -c $(PY_CORE_CFLAGS) \
+		-DSHLIB_SUFFIX='"$(SHLIB_SUFFIX)"' \
+		-DEXT_SUFFIX='"$(EXT_SUFFIX)"' \
+		-o $@ $(srcdir)/Python/dynload_win.c
+
 Python/sysmodule.o: $(srcdir)/Python/sysmodule.c Makefile
 	$(CC) -c $(PY_CORE_CFLAGS) \
 		-DABIFLAGS='"$(ABIFLAGS)"' \

Python/dynload_win.c

@@ -35,9 +35,20 @@ void _Py_DeactivateActCtx(ULONG_PTR cookie);
 const char *_PyImport_DynLoadFiletab[] = {
     PYD_TAGGED_SUFFIX,
     PYD_UNTAGGED_SUFFIX,
+#ifdef EXT_SUFFIX
+    EXT_SUFFIX, /* include SOABI flags where is encoded debug */
+#endif
+#ifdef SHLIB_SUFFIX
+    "-abi" PYTHON_ABI_STRING SHLIB_SUFFIX,
+#endif
     NULL
 };
 
+
+#if defined(__MINGW32__)
+/* avoid compile error: conflicting types for 'strcasecmp' */
+#  define strcasecmp fake_strcasecmp
+#endif
 /* Case insensitive string compare, to avoid any dependencies on particular
    C RTL implementations */
 

configure.ac

@@ -2641,6 +2641,9 @@ if test -z "$SHLIB_SUFFIX"; then
 	CYGWIN*)   SHLIB_SUFFIX=.dll;;
 	*)	   SHLIB_SUFFIX=.so;;
 	esac
+	case $host_os in
+	mingw*)    SHLIB_SUFFIX=.dll;;
+	esac
 fi
 AC_MSG_RESULT($SHLIB_SUFFIX)
 
@@ -3679,6 +3682,12 @@ then
 	fi
 	;;
 	esac
+	case $host in
+	*-*-mingw*)
+	DYNLOADFILE="dynload_win.o"
+	extra_machdep_objs="$extra_machdep_objs PC/dl_nt.o"
+	;;
+	esac
 fi
 AC_MSG_RESULT($DYNLOADFILE)
 if test "$DYNLOADFILE" != "dynload_stub.o"
@@ -4920,6 +4929,13 @@ case $ac_sys_system in
 	EXT_SUFFIX=${SHLIB_SUFFIX};;
 esac
 
+case $host_os in
+    mingw*)
+	dnl Synchronized with _PyImport_DynLoadFiletab (dynload_win.c)
+	dnl Do not use more then one dot on this platform !
+	EXT_SUFFIX=-$SOABI$SHLIB_SUFFIX;;
+esac
+
 AC_MSG_CHECKING(LDVERSION)
 LDVERSION='$(VERSION)$(ABIFLAGS)'
 AC_MSG_RESULT($LDVERSION)