Hash all arguments for pch and add -fpch-preprocess if a .gch is found

diff --git a/ccache.c b/ccache.c
index 1fe0501d18e8530cfa024ff0507ad44383104d20..854d289d74476d4aa484b48a0e8a4a6c33ad8822 100644 (file)
--- a/ccache.c
+++ b/ccache.c
@@ -189,6 +189,9 @@ static int nlevels = 2;
  */
 static int compile_preprocessed_source_code;
 
+/* Whether the output is a precompiled header */
+static int output_is_precompiled_header = 0;
+
 /* How long (in microseconds) to wait before breaking a stale lock. */
 unsigned lock_staleness_limit = 2000000;
 
@@ -1014,8 +1017,8 @@ calculate_object_hash(struct args *args, struct mdfour *hash, int direct_mode)
                /* When using the preprocessor, 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. */
-               if (!direct_mode) {
+                  all. For precompiled headers this might not be the case. */
+               if (!direct_mode && !output_is_precompiled_header) {
                        if (i < args->argc-1) {
                                if (str_eq(args->argv[i], "-D") ||
                                    str_eq(args->argv[i], "-I") ||
@@ -1337,7 +1340,7 @@ cc_process_args(struct args *orig_args, struct args **preprocessor_args,
        int found_c_opt = 0;
        int found_S_opt = 0;
        int found_arch_opt = 0;
-       int output_is_precompiled_header = 0;
+       int found_pch = 0;
        const char *explicit_language = NULL; /* As specified with -x. */
        const char *file_language;            /* As deduced from file extension. */
        const char *actual_language;          /* Language to actually use. */
@@ -1577,6 +1580,7 @@ cc_process_args(struct args *orig_args, struct args **preprocessor_args,
                        };
                        int j;
                        char *relpath;
+                       char *pchpath;
                        for (j = 0; opts[j]; j++) {
                                if (str_eq(argv[i], opts[j])) {
                                        if (i == argc-1) {
@@ -1589,6 +1593,14 @@ cc_process_args(struct args *orig_args, struct args **preprocessor_args,
                                        args_add(stripped_args, argv[i]);
                                        relpath = make_relative_path(x_strdup(argv[i+1]));
                                        args_add(stripped_args, relpath);
+
+                                       /* Try to be smart about detecting precompiled headers */
+                                       pchpath = format("%s.gch", argv[i+1]);
+                                       if (stat(pchpath, &st) == 0 && S_ISDIR(st.st_mode)) {
+                                               found_pch = 1;
+                                       }
+
+                                       free(pchpath);
                                        free(relpath);
                                        i++;
                                        break;
@@ -1811,6 +1823,10 @@ cc_process_args(struct args *orig_args, struct args **preprocessor_args,
        if (input_charset) {
                args_add(*preprocessor_args, input_charset);
        }
+       if (found_pch) {
+               cc_log("Use of precompiled header detected, adding -fpch-preprocess");
+               args_add(*preprocessor_args, "-fpch-preprocess");
+       }
        if (explicit_language) {
                args_add(*preprocessor_args, "-x");
                args_add(*preprocessor_args, explicit_language);