Handle non-extern declarations after extern declarations correctly, warn about redund...

[r18438]

diff --git a/parser.c b/parser.c
index 77a7036..404da65 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -434,6 +434,54 @@ static declaration_t *stack_push(stack_entry_t **stack_ptr,
                                        "of type ");
                        print_type_quoted(previous_declaration->type);
                        fputc('\n', stderr);
+               } else {
+                       const storage_class_t old_storage = previous_declaration->storage_class;
+                       const storage_class_t new_storage = declaration->storage_class;
+                       if (current_function == NULL) {
+                               if (old_storage != STORAGE_CLASS_STATIC &&
+                                   new_storage == STORAGE_CLASS_STATIC) {
+                                       parser_print_error_prefix_pos(declaration->source_position);
+                                       fprintf(stderr,
+                                               "static declaration of '%s' follows non-static declaration\n",
+                                               symbol->string);
+                                       parser_print_error_prefix_pos(previous_declaration->source_position);
+                                       fprintf(stderr, "previous declaration of '%s' was here\n",
+                                               symbol->string);
+                               } else {
+                                       if (old_storage == STORAGE_CLASS_EXTERN) {
+                                               if (new_storage == STORAGE_CLASS_NONE) {
+                                                       previous_declaration->storage_class = STORAGE_CLASS_NONE;
+                                               }
+                                       } else {
+                                               parser_print_warning_prefix_pos(declaration->source_position);
+                                               fprintf(stderr, "redundant declaration for '%s'\n",
+                                                                               symbol->string);
+                                               parser_print_warning_prefix_pos(previous_declaration->source_position);
+                                               fprintf(stderr, "previous declaration of '%s' was here\n",
+                                                                               symbol->string);
+                                       }
+                               }
+                       } else {
+                               if (old_storage == STORAGE_CLASS_EXTERN &&
+                                               new_storage == STORAGE_CLASS_EXTERN) {
+                                       parser_print_warning_prefix_pos(declaration->source_position);
+                                       fprintf(stderr, "redundant extern declaration for '%s'\n",
+                                               symbol->string);
+                                       parser_print_warning_prefix_pos(previous_declaration->source_position);
+                                       fprintf(stderr, "previous declaration of '%s' was here\n",
+                                               symbol->string);
+                               } else {
+                                       parser_print_error_prefix_pos(declaration->source_position);
+                                       if (old_storage == new_storage) {
+                                               fprintf(stderr, "redeclaration of '%s'\n", symbol->string);
+                                       } else {
+                                               fprintf(stderr, "redeclaration of '%s' with different linkage\n", symbol->string);
+                                       }
+                                       parser_print_error_prefix_pos(previous_declaration->source_position);
+                                       fprintf(stderr, "previous declaration of '%s' was here\n",
+                                               symbol->string);
+                               }
+                       }
                }
                return previous_declaration;
        }