diff --git a/xpcom/libxpt/xptcall/src/md/unix/Makefile.in b/xpcom/libxpt/xptcall/src/md/unix/Makefile.in
index df66b14c0c94..29aa04654bb8 100644
--- a/xpcom/libxpt/xptcall/src/md/unix/Makefile.in
+++ b/xpcom/libxpt/xptcall/src/md/unix/Makefile.in
@@ -34,7 +34,7 @@ CPPSRCS		= \
 		  $(NULL)
 
 # SunOS i86pc should use the intel code too.
-ifneq (,$(filter SunOS Linux FreeBSD NetBSD BSD_OS,$(OS_ARCH)))
+ifneq (,$(filter SunOS Linux FreeBSD NetBSD OpenBSD BSD_OS,$(OS_ARCH)))
 ifeq (86,$(findstring 86,$(OS_TEST)))
 CPPSRCS		= \
 		  xptcinvoke_unixish_x86.cpp \
diff --git a/xpcom/reflect/xptcall/src/md/unix/Makefile.in b/xpcom/reflect/xptcall/src/md/unix/Makefile.in
index df66b14c0c94..29aa04654bb8 100644
--- a/xpcom/reflect/xptcall/src/md/unix/Makefile.in
+++ b/xpcom/reflect/xptcall/src/md/unix/Makefile.in
@@ -34,7 +34,7 @@ CPPSRCS		= \
 		  $(NULL)
 
 # SunOS i86pc should use the intel code too.
-ifneq (,$(filter SunOS Linux FreeBSD NetBSD BSD_OS,$(OS_ARCH)))
+ifneq (,$(filter SunOS Linux FreeBSD NetBSD OpenBSD BSD_OS,$(OS_ARCH)))
 ifeq (86,$(findstring 86,$(OS_TEST)))
 CPPSRCS		= \
 		  xptcinvoke_unixish_x86.cpp \