From db850f37a2a284bf18cea427e4676a22d83d04b8 Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@cs.stanford.edu>
Date: Tue, 18 Aug 2020 12:38:21 +0900
Subject: [PATCH] Add -MT option

---
 main.c         | 13 +++++++++++--
 test/driver.sh |  6 ++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/main.c b/main.c
index 00eee92..d991d8a 100644
--- a/main.c
+++ b/main.c
@@ -17,6 +17,7 @@ static bool opt_c;
 static bool opt_cc1;
 static bool opt_hash_hash_hash;
 static char *opt_MF;
+static char *opt_MT;
 static char *opt_o;
 
 static StringArray ld_extra_args;
@@ -33,7 +34,7 @@ static void usage(int status) {
 }
 
 static bool take_arg(char *arg) {
-  char *x[] = {"-o", "-I", "-idirafter", "-include", "-x", "-MF"};
+  char *x[] = {"-o", "-I", "-idirafter", "-include", "-x", "-MF", "-MT"};
 
   for (int i = 0; i < sizeof(x) / sizeof(*x); i++)
     if (!strcmp(arg, x[i]))
@@ -194,6 +195,14 @@ static void parse_args(int argc, char **argv) {
       continue;
     }
 
+    if (!strcmp(argv[i], "-MT")) {
+      if (opt_MT == NULL)
+        opt_MT = argv[++i];
+      else
+        opt_MT = format("%s %s", opt_MT, argv[++i]);
+      continue;
+    }
+
     if (!strcmp(argv[i], "-cc1-input")) {
       base_file = argv[++i];
       continue;
@@ -357,7 +366,7 @@ static void print_dependencies(void) {
     path = "-";
 
   FILE *out = open_file(path);
-  fprintf(out, "%s:", replace_extn(base_file, ".o"));
+  fprintf(out, "%s:", opt_MT ? opt_MT : replace_extn(base_file, ".o"));
 
   File **files = get_input_files();
 
diff --git a/test/driver.sh b/test/driver.sh
index b870846..152e83a 100755
--- a/test/driver.sh
+++ b/test/driver.sh
@@ -240,4 +240,10 @@ check -MP
 grep -q '^.*/out3.h:' $tmp/mp
 check -MP
 
+# -MT
+$chibicc -MT foo -M -I$tmp $tmp/out.c | grep -q '^foo:'
+check -MT
+$chibicc -MT foo -MT bar -M -I$tmp $tmp/out.c | grep -q '^foo bar:'
+check -MT
+
 echo OK