diff --git a/libexec/trick/make_makefile_swig b/libexec/trick/make_makefile_swig
index 50cf32a9..cc05f7e1 100755
--- a/libexec/trick/make_makefile_swig
+++ b/libexec/trick/make_makefile_swig
@@ -116,9 +116,18 @@ sub read_files_to_process() {
     }
 
     open FILE, "build/ICG_ext_lib" or die 'could not open build/ICG_ext_lib' ;
-    @ext_lib_files = <FILE> ;
+    my @unfiltered_ext_lib_files = <FILE> ;
+    @unfiltered_ext_lib_files = <FILE> ;
     close FILE ;
-    chomp @ext_lib_files ;
+    chomp @unfiltered_ext_lib_files ;
+
+    foreach my $e ( @unfiltered_ext_lib_files ) {
+        $e = abs_path(dirname($e)) . "/" . basename($e) ;
+        if ( exists $compiler_file_list{$e} ) {
+            push @ext_lib_files , $e ;
+        }
+    }
+
 }
 
 sub make_swig_makefile() {
@@ -289,7 +298,7 @@ LINK_OBJECTS += \$(SWIG_MODULE_OBJECTS)
     print MAKEFILE "S_main: \$(TRICK_FIXED_PYTHON)\n\n" ;
 
     print MAKEFILE "\$(TRICK_FIXED_PYTHON) : $swig_sim_dir/\% : \${TRICK_HOME}/share/trick/swig/\%\n" ;
-    print MAKEFILE "\t\$(ECHO_CMD)/bin/cp \$< \$@\n\n" ;
+    print MAKEFILE "\t\$(ECHO_CMD)/bin/cp -f \$< \$@\n\n" ;
 
     foreach (keys %swig_dirs) {
         print MAKEFILE "$_:\n" ;
diff --git a/share/trick/makefiles/Makefile.sim b/share/trick/makefiles/Makefile.sim
index 4b01aebe..849cfa32 100644
--- a/share/trick/makefiles/Makefile.sim
+++ b/share/trick/makefiles/Makefile.sim
@@ -45,7 +45,7 @@ ${TRICK_LIB_DIR}/libtrick.a:
 	@exit -1
 
 # CP creates S_source.hh required for ICG and SWIG processing
-S_source.hh : S_define | build
+S_source.hh $(CURDIR)/build/S_define.lib_deps : S_define | build
 	$(PRINT_CP)
 	$(ECHO_CMD)${TRICK_HOME}/$(LIBEXEC)/trick/configuration_processor $(TRICK_CPFLAGS)
 
@@ -68,7 +68,7 @@ $(CURDIR)/build/S_define.deps :
 	$(ECHO_CMD)$(TRICK_CPPC) $(TRICK_SFLAGS) $(TRICK_SYSTEM_SFLAGS) -M -MT S_source.hh -MF build/S_define.deps -x c++ S_define
 
 # Create makefile for source code
-$(CURDIR)/build/Makefile_src: | $(CURDIR)/build/Makefile_io_src
+$(CURDIR)/build/Makefile_src: | $(CURDIR)/build/Makefile_io_src $(CURDIR)/build/S_define.lib_deps
 	$(PRINT_MAKEFILE_SRC)
 	$(ECHO_CMD)${TRICK_HOME}/$(LIBEXEC)/trick/make_makefile_src $?