implemented the identargs idea from compilercache

diff --git a/ccache.c b/ccache.c
index cacecf3d3b29239e174f2b137735654fe22c73de..27e2a4061e7999ef746c42ecaeeb7d826133e36d 100644 (file)
--- a/ccache.c
+++ b/ccache.c
@@ -158,6 +158,26 @@ static void find_hash(ARGS *args)
 
        /* first the arguments */
        for (i=0;i<args->argc;i++) {
+               /* some arguments don't contribute to the hash. The
+                  theory is that these arguments will change the
+                  output of -E if they are going to have any effect
+                  at all, or they only affect linking */
+               if (i < args->argc-1) {
+                       if (strcmp(args->argv[i], "-I") == 0 ||
+                           strcmp(args->argv[i], "-include") == 0 ||
+                           strcmp(args->argv[i], "-L") == 0 ||
+                           strcmp(args->argv[i], "-D") == 0 ||
+                           strcmp(args->argv[i], "-isystem") == 0) {
+                               i++;
+                               continue;
+                       }
+                       if (strncmp(args->argv[i], "-I", 2) == 0 ||
+                           strncmp(args->argv[i], "-L", 2) == 0 ||
+                           strncmp(args->argv[i], "-D", 2) == 0) {
+                               continue;
+                       }
+               }
+
                hash_string(args->argv[i]);
        }