diff --git a/xpcom/reflect/xptcall/src/md/unix/moz.build b/xpcom/reflect/xptcall/src/md/unix/moz.build
index 202aaf24397c..fa173b3f578c 100644
--- a/xpcom/reflect/xptcall/src/md/unix/moz.build
+++ b/xpcom/reflect/xptcall/src/md/unix/moz.build
@@ -7,17 +7,10 @@
 MODULE = 'xpcom'
 
 if CONFIG['OS_ARCH'] == 'Darwin':
-    if CONFIG['OS_TEST'].find('86') != -1:
-        if CONFIG['OS_TEST'] == 'x86_64':
-            CPP_SOURCES += [
-                'xptcinvoke_x86_64_unix.cpp',
-                'xptcstubs_x86_64_darwin.cpp',
-            ]
-        else:
-            CPP_SOURCES += [
-                'xptcinvoke_gcc_x86_unix.cpp',
-                'xptcstubs_gcc_x86_unix.cpp',
-            ]
+    CPP_SOURCES += [
+        'xptcinvoke_darwin.cpp',
+        'xptcstubs_darwin.cpp',
+    ]
 
 if CONFIG['OS_ARCH'] in ('NetBSD', 'OpenBSD', 'GNU'):
     if CONFIG['CPU_ARCH'] == 'x86':
@@ -211,12 +204,6 @@ if CONFIG['OS_ARCH'] == 'OpenBSD' and CONFIG['OS_TEST'] == 'powerpc':
         'xptcstubs_ppc_openbsd.cpp',
     ]
 
-if CONFIG['OS_ARCH'] == 'Darwin' and CONFIG['TARGET_CPU'] == 'powerpc':
-    CPP_SOURCES += [
-        'xptcinvoke_ppc_rhapsody.cpp',
-        'xptcstubs_ppc_rhapsody.cpp',
-    ]
-
 if CONFIG['OS_ARCH'] == 'Linux' and CONFIG['OS_TEST'].find('sparc') != -1:
     CPP_SOURCES += [
         'xptcinvoke_sparc_solaris.cpp',
diff --git a/xpcom/reflect/xptcall/src/md/unix/xptcinvoke_darwin.cpp b/xpcom/reflect/xptcall/src/md/unix/xptcinvoke_darwin.cpp
new file mode 100644
index 000000000000..887f5f8c49fc
--- /dev/null
+++ b/xpcom/reflect/xptcall/src/md/unix/xptcinvoke_darwin.cpp
@@ -0,0 +1,14 @@
+/* -*- Mode: C -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#if defined(__i386__)
+#include "xptcinvoke_gcc_x86_unix.cpp"
+#elif defined(__x86_64__)
+#include "xptcinvoke_x86_64_unix.cpp"
+#elif defined(__ppc__)
+#include "xptcinvoke_ppc_rhapsody.cpp"
+#else
+#error unknown cpu architecture
+#endif
diff --git a/xpcom/reflect/xptcall/src/md/unix/xptcstubs_darwin.cpp b/xpcom/reflect/xptcall/src/md/unix/xptcstubs_darwin.cpp
new file mode 100644
index 000000000000..26af1561bea2
--- /dev/null
+++ b/xpcom/reflect/xptcall/src/md/unix/xptcstubs_darwin.cpp
@@ -0,0 +1,14 @@
+/* -*- Mode: C -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#if defined(__i386__)
+#include "xptcstubs_gcc_x86_unix.cpp"
+#elif defined(__x86_64__)
+#include "xptcstubs_x86_64_darwin.cpp"
+#elif defined(__ppc__)
+#include "xptcstubs_ppc_rhapsody.cpp"
+#else
+#error unknown cpu architecture
+#endif