diff --git a/src/idl/CMakeLists.txt b/src/idl/CMakeLists.txt
index aa7caff31f..65abc0f29c 100644
--- a/src/idl/CMakeLists.txt
+++ b/src/idl/CMakeLists.txt
@@ -49,7 +49,6 @@ add_library(
     src/string.c
     src/annotation.c
     src/scope.c
-    src/hashid.c
     src/string.c
     src/tree.c
     src/visit.c
diff --git a/src/idl/src/directive.c b/src/idl/src/directive.c
index f98589ab95..958e13646a 100644
--- a/src/idl/src/directive.c
+++ b/src/idl/src/directive.c
@@ -563,6 +563,10 @@ idl_retcode_t idl_parse_directive(idl_pstate_t *pstate, idl_token_t *tok)
     return parse_line(pstate, tok);
   } else if ((pstate->scanner.state & IDL_SCAN_KEYLIST) == IDL_SCAN_KEYLIST) {
     return parse_keylist(pstate, tok);
+  } else if (pstate->scanner.state == IDL_SCAN_UNKNOWN_PRAGMA) {
+    if (tok->code == '\n')
+      pstate->scanner.state = IDL_SCAN;
+    return IDL_RETCODE_OK;
   } else if (pstate->scanner.state == IDL_SCAN_PRAGMA) {
     /* expect keylist */
     if (tok->code == IDL_TOKEN_IDENTIFIER) {
@@ -576,10 +580,9 @@ idl_retcode_t idl_parse_directive(idl_pstate_t *pstate, idl_token_t *tok)
         pstate->scanner.state = IDL_SCAN_KEYLIST;
         return IDL_RETCODE_OK;
       }
-      idl_error(pstate, &tok->location,
-        "Unsupported #pragma directive %s", tok->value.str);
-      return IDL_RETCODE_SYNTAX_ERROR;
     }
+    pstate->scanner.state = IDL_SCAN_UNKNOWN_PRAGMA;
+    return IDL_RETCODE_OK;
   } else if (pstate->scanner.state == IDL_SCAN_DIRECTIVE_NAME) {
     if (tok->code == IDL_TOKEN_PP_NUMBER) {
       /* expect linemarker */
diff --git a/src/idl/tests/pragma.c b/src/idl/tests/pragma.c
index 62fdde1d74..030c61ec75 100644
--- a/src/idl/tests/pragma.c
+++ b/src/idl/tests/pragma.c
@@ -139,3 +139,19 @@ CU_Test(idl_pragma, keylist_outer_scope)
   CU_ASSERT((idl_mask(s1->keylist) & IDL_KEYLIST) != 0);
   idl_delete_pstate(pstate);
 }
+
+CU_Test(idl_pragma, unknown)
+{
+  idl_retcode_t ret;
+  idl_pstate_t *pstate = NULL;
+  idl_struct_t *s1;
+  static const char str[] = "struct s1 { char c; };\n"
+                            "#pragma foo \"bar::baz\"";
+
+  ret = parse_string(str, &pstate);
+  CU_ASSERT_EQUAL_FATAL(ret, IDL_RETCODE_OK);
+  CU_ASSERT_PTR_NOT_NULL_FATAL(pstate);
+  s1 = (idl_struct_t *)pstate->root;
+  CU_ASSERT_FATAL(idl_is_struct(s1));
+  idl_delete_pstate(pstate);
+}
diff --git a/src/tools/idlc/src/idlc.c b/src/tools/idlc/src/idlc.c
index c78293e797..0af7820868 100644
--- a/src/tools/idlc/src/idlc.c
+++ b/src/tools/idlc/src/idlc.c
@@ -302,8 +302,8 @@ static idl_retcode_t idlc_parse(void)
     if (mcpp_lib_main(config.argc, config.argv) == 0) {
       assert(!config.compile || retcode == IDL_RETCODE_OK);
     } else if (config.compile) {
-      assert(retcode != IDL_RETCODE_OK);
-      ret = retcode;
+      /* retcode is not set on preprocessor error */
+      ret = retcode ? retcode : IDL_RETCODE_SYNTAX_ERROR;
     }
     if (pstate) {
       pstate->flags &= ~IDL_WRITE;
@@ -576,7 +576,9 @@ int main(int argc, char *argv[])
     config.file = argv[optind];
     config.argv[config.argc++] = config.file;
     if ((ret = idlc_parse())) {
-      fprintf(stderr, "Cannot parse '%s'\n", config.file);
+      /* assume other errors are reported by processor */
+      if (ret == IDL_RETCODE_NO_MEMORY)
+        fprintf(stderr, "Out of memory\n");
       goto err_parse;
     } else if (config.compile) {
       if (gen.generate)