From: Christoph Mallon <christoph.mallon@gmx.de>
Date: Tue, 13 Nov 2007 21:06:52 +0000 (+0000)
Subject: Handle non-void functions which miss a return statement at the end.  Especially handl... 
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=bfe76ff46dbc10738f330e87edc21f6b55875a20;p=cparser

Handle non-void functions which miss a return statement at the end.  Especially handle the special case of main() returning 0.

[r18384]
---

diff --git a/ast2firm.c b/ast2firm.c
index 62793e5..ebe3957 100644
--- a/ast2firm.c
+++ b/ast2firm.c
@@ -1532,7 +1532,22 @@ static void create_function(declaration_t *declaration)
 
 	/* do we have a return statement yet? */
 	if(get_cur_block() != NULL) {
-		ir_node *ret = new_Return(get_store(), 0, NULL);
+		assert(declaration->type->type == TYPE_FUNCTION);
+		const function_type_t* const func_type = (const function_type_t*)declaration->type;
+		ir_node *ret;
+		if (func_type->result_type == type_void) {
+			ret = new_Return(get_store(), 0, NULL);
+		} else {
+			ir_mode *const mode = get_ir_mode(func_type->result_type);
+			ir_node *      in[1];
+			// §5.1.2.2.3 main implicitly returns 0
+			if (strcmp(declaration->symbol->string, "main") == 0) {
+				in[0] = new_Const(mode, get_mode_null(mode));
+			} else {
+				in[0] = new_Unknown(mode);
+			}
+			ret = new_Return(get_store(), 1, in);
+		}
 		add_immBlock_pred(end_block, ret);
 	}