2 files changed, 6 insertions, 1 deletions
diff --git a/libtcc.c b/libtcc.c
index e538321..64e5519 100644
--- a/libtcc.c
+++ b/libtcc.c
@@ -1274,7 +1274,7 @@ LIBTCCAPI int tcc_set_output_type(TCCState *s, int output_type)
 
     if (!s->nostdinc) {
         /* default include paths */
-        /* XXX: reverse order needed if -isystem support */
+        /* -isystem paths have already been handled */
 #ifndef TCC_TARGET_PE
         tcc_add_sysinclude_path(s, CONFIG_SYSROOT "/usr/local/include");
         tcc_add_sysinclude_path(s, CONFIG_SYSROOT "/usr/include");
diff --git a/tcc.c b/tcc.c
index e0d6386..549b012 100644
--- a/tcc.c
+++ b/tcc.c
@@ -111,6 +111,7 @@ enum {
     TCC_OPTION_O,
     TCC_OPTION_m,
     TCC_OPTION_f,
+    TCC_OPTION_isystem,
     TCC_OPTION_nostdinc,
     TCC_OPTION_nostdlib,
     TCC_OPTION_print_search_dirs,
@@ -161,6 +162,7 @@ static const TCCOption tcc_options[] = {
     { "O", TCC_OPTION_O, TCC_OPTION_HAS_ARG | TCC_OPTION_NOSEP },
     { "m", TCC_OPTION_m, TCC_OPTION_HAS_ARG },
     { "f", TCC_OPTION_f, TCC_OPTION_HAS_ARG | TCC_OPTION_NOSEP },
+    { "isystem", TCC_OPTION_isystem, TCC_OPTION_HAS_ARG },
     { "nostdinc", TCC_OPTION_nostdinc, 0 },
     { "nostdlib", TCC_OPTION_nostdlib, 0 },
     { "print-search-dirs", TCC_OPTION_print_search_dirs, 0 }, 
@@ -425,6 +427,9 @@ static int parse_args(TCCState *s, int argc, char **argv)
                 reloc_output = 1;
                 output_type = TCC_OUTPUT_OBJ;
                 break;
+            case TCC_OPTION_isystem:
+                tcc_add_sysinclude_path(s, optarg);
+                break;
             case TCC_OPTION_nostdinc:
                 s->nostdinc = 1;
                 break;