From 953a820405dfd857ff9f5e24f3b630b6103dad46 Mon Sep 17 00:00:00 2001
From: Michael Beck <beck@ipd.info.uni-karlsruhe.de>
Date: Tue, 16 Sep 2008 02:09:35 +0000
Subject: [PATCH] - when parsing compound types, do NOT destroy old
 declarations if   a new one with the same name is found, always create a new
 one - handle enums analog - do not record "anonymous declarations" in the AST

[r21986]
---
 parser.c | 82 ++++++++++++++++++++++++++++++--------------------------
 1 file changed, 44 insertions(+), 38 deletions(-)

diff --git a/parser.c b/parser.c
index 1ccaffa..c4523d8 100644
--- a/parser.c
+++ b/parser.c
@@ -2697,7 +2697,6 @@ static declaration_t *parse_compound_type_specifier(bool is_struct)
 				errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
 				       is_struct ? "struct" : "union", symbol,
 				       &declaration->source_position);
-				declaration->scope.declarations = NULL;
 			}
 		}
 	} else if (token.type != '{') {
@@ -2712,18 +2711,17 @@ static declaration_t *parse_compound_type_specifier(bool is_struct)
 		return NULL;
 	}
 
-	if (declaration == NULL) {
-		declaration = allocate_declaration_zero();
-		declaration->namespc         =
-			(is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
-		declaration->source_position = token.source_position;
-		declaration->symbol          = symbol;
-		declaration->parent_scope    = scope;
-		if (symbol != NULL) {
-			environment_push(declaration);
-		}
-		append_declaration(declaration);
+	/* always create a new declaration, do NOT modify old one */
+	declaration = allocate_declaration_zero();
+	declaration->namespc         =
+		(is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
+	declaration->source_position = token.source_position;
+	declaration->symbol          = symbol;
+	declaration->parent_scope    = scope;
+	if (symbol != NULL) {
+		environment_push(declaration);
 	}
+	append_declaration(declaration);
 
 	if (token.type == '{') {
 		declaration->init.complete = true;
@@ -2786,11 +2784,14 @@ end_error:
 	;
 }
 
+/**
+ * Parse enum specifier and return the enum type or NULL on error.
+ */
 static type_t *parse_enum_specifier(void)
 {
-	gnu_attribute_t *attributes = NULL;
-	declaration_t   *declaration;
-	symbol_t        *symbol;
+	gnu_attribute_t *attributes  = NULL;
+	declaration_t   *declaration = NULL;
+	symbol_t        *symbol      = NULL;
 
 	eat(T_enum);
 	if (token.type == T_IDENTIFIER) {
@@ -2802,30 +2803,31 @@ static type_t *parse_enum_specifier(void)
 		parse_error_expected("while parsing enum type specifier",
 		                     T_IDENTIFIER, '{', NULL);
 		return NULL;
-	} else {
-		declaration = NULL;
-		symbol      = NULL;
 	}
 
-	if (declaration == NULL) {
-		declaration = allocate_declaration_zero();
-		declaration->namespc         = NAMESPACE_ENUM;
-		declaration->source_position = token.source_position;
-		declaration->symbol          = symbol;
-		declaration->parent_scope  = scope;
+	if (token.type == '{' && declaration != NULL && declaration->init.complete) {
+		errorf(HERE, "multiple definitions of enum '%Y' (previous definition at %P)",
+			symbol, &declaration->source_position);
 	}
 
+	declaration = allocate_declaration_zero();
+	declaration->namespc         = NAMESPACE_ENUM;
+	declaration->source_position = token.source_position;
+	declaration->symbol          = symbol;
+	declaration->parent_scope    = scope;
+	if (symbol != NULL) {
+		environment_push(declaration);
+	}
+	append_declaration(declaration);
+
 	type_t *const type      = allocate_type_zero(TYPE_ENUM, &declaration->source_position);
 	type->enumt.declaration = declaration;
 
 	if (token.type == '{') {
 		if (declaration->init.complete) {
-			errorf(HERE, "multiple definitions of enum %Y", symbol);
+			errorf(HERE, "multiple definitions of enum '%Y' (previous definition at %P)",
+			       symbol, &declaration->source_position);
 		}
-		if (symbol != NULL) {
-			environment_push(declaration);
-		}
-		append_declaration(declaration);
 		declaration->init.complete = true;
 
 		parse_enum_entries(type);
@@ -4601,24 +4603,26 @@ static void parse_anonymous_declaration_rest(
 {
 	eat(';');
 
+	if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) {
+		warningf(&specifiers->source_position,
+			"useless storage class in empty declaration");
+	}
+
+#ifdef RECORD_EMPTY_DECLARARTIONS
 	declaration_t *const declaration    = allocate_declaration_zero();
 	declaration->type                   = specifiers->type;
 	declaration->declared_storage_class = specifiers->declared_storage_class;
 	declaration->source_position        = specifiers->source_position;
 	declaration->modifiers              = specifiers->modifiers;
+	declaration->storage_class          = STORAGE_CLASS_NONE;
+#endif
 
-	if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
-		warningf(&declaration->source_position,
-		         "useless storage class in empty declaration");
-	}
-	declaration->storage_class = STORAGE_CLASS_NONE;
-
-	type_t *type = declaration->type;
+	type_t *type = specifiers->type;
 	switch (type->kind) {
 		case TYPE_COMPOUND_STRUCT:
 		case TYPE_COMPOUND_UNION: {
 			if (type->compound.declaration->symbol == NULL) {
-				warningf(&declaration->source_position,
+				warningf(&specifiers->source_position,
 				         "unnamed struct/union that defines no instances");
 			}
 			break;
@@ -4628,11 +4632,13 @@ static void parse_anonymous_declaration_rest(
 			break;
 
 		default:
-			warningf(&declaration->source_position, "empty declaration");
+			warningf(&specifiers->source_position, "empty declaration");
 			break;
 	}
 
+#ifdef RECORD_EMPTY_DECLARARTIONS
 	append_declaration(declaration);
+#endif
 }
 
 static void parse_declaration_rest(declaration_t *ndeclaration,
-- 
2.20.1