0008-reproducible-build.patch

--- ikarus-0.0.3+bzr.2010.01.26.orig/src/ikarus-runtime.c
+++ ikarus-0.0.3+bzr.2010.01.26/src/ikarus-runtime.c
@@ -810,8 +810,36 @@ ikptr
 ikrt_bvftime(ikptr outbv, ikptr fmtbv){
   time_t t;
   struct tm* tmp;
-  t = time(NULL);
-  tmp = localtime(&t);
+  char *endptr;
+  char *source_date_epoch;
+  unsigned long long epoch;
+
+  source_date_epoch = getenv("SOURCE_DATE_EPOCH");
+  if (source_date_epoch) {
+    errno = 0;
+    epoch = strtoull(source_date_epoch, &endptr, 10);
+    if ((errno == ERANGE && (epoch == ULLONG_MAX || epoch == 0))
+        || (errno != 0 && epoch == 0)) {
+      fprintf(stderr, "Environment variable $SOURCE_DATE_EPOCH: strtoull: %s\n", strerror(errno));
+      exit(EXIT_FAILURE);
+    }
+    if (endptr == source_date_epoch) {
+      printf(stderr, "Environment variable $SOURCE_DATE_EPOCH: No digits were found: %s\n", endptr);
+      exit(EXIT_FAILURE);
+    }
+    if (*endptr != '\0') {
+      fprintf(stderr, "Environment variable $SOURCE_DATE_EPOCH: Trailing garbage: %s\n", endptr);
+      exit(EXIT_FAILURE);
+    }
+    if (epoch > ULONG_MAX) {
+      fprintf(stderr, "Environment variable $SOURCE_DATE_EPOCH: value must be smaller than or equal to: %lu but was found to be: %llu \n", ULONG_MAX, epoch);
+      exit(EXIT_FAILURE);
+    }
+    t = epoch;
+  } else {
+    t = time(NULL);
+  }
+  tmp = gmtime(&t);
   if(tmp == NULL){
     fprintf(stderr, "Error in time: %s\n", strerror(errno));
   }