#220: autotools not building DLL using msys2 and mingw64 on windows 10

configure.ac

@@ -79,4 +79,20 @@ AC_FUNC_ALLOCA
 
 AC_CONFIG_FILES([Makefile src/Makefile test/Makefile sample/Makefile onig-config])
 AC_CONFIG_COMMANDS([default],[chmod +x onig-config],[])
+
+# for Issue #220
+FIX_TO_LDFLAGS=
+EXPORT_ALL_SYMBOLS=
+case $host_os in
+  cygwin* | mingw* )
+    if test X"$enable_shared" = Xyes; then
+      FIX_TO_LDFLAGS="-no-undefined"
+      EXPORT_ALL_SYMBOLS="-Wl,--export-all-symbols"
+    fi
+    ;;
+esac
+
+EXTRA_LIBONIG_LDFLAGS="$EXTRA_LIBONIG_LDFLAGS $FIX_TO_LDFLAGS"
+AC_SUBST(EXTRA_LIBONIG_LDFLAGS)
+
 AC_OUTPUT

src/Makefile.am

@@ -50,7 +50,7 @@ libonig_la_SOURCES = regint.h regparse.h regenc.h st.h \
 	gb18030.c koi8_r.c cp1251.c \
 	onig_init.c
 
-libonig_la_LDFLAGS = -version-info $(LTVERSION)
+libonig_la_LDFLAGS = $(EXTRA_LIBONIG_LDFLAGS) -version-info $(LTVERSION)
 
 EXTRA_DIST = koi8.c mktable.c \
 	unicode_fold_data.c unicode_property_data.c \