scc

commit 94615c26e61ff331100b39816cf2b4ea82dc4bd7
parent cdafe864ddbdca6af43660f88bff661afb6b42de
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Wed, 16 Apr 2014 11:48:40 +0200

Add void pointers

These pointers can be mixed with pointers of any type.

Diffstat:
M
cc.h
 | 
2
+-
M
expr.c
 | 
3
+++
M
types.c
 | 
6
++++++

3 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/cc.h b/cc.h
@@ -113,7 +113,7 @@ extern void context(void (*fun)(void));
 
 extern Type *typename(void);
 
-extern Type *voidtype, *booltype,
+extern Type *voidtype, *pvoidtype, *booltype,
 	*uchartype,   *chartype,
 	*uinttype,    *inttype,
 	*ushortype,   *shortype,
diff --git a/expr.c b/expr.c
@@ -117,6 +117,9 @@ convert(Node *np, Type *tp1)
 		switch (t2) {
 		case ARY: case FTN:
 			np = addr2ptr(np);
+		case PTR:
+			if (tp1 != pvoidtype && tp2 != pvoidtype)
+				return NULL;
 			/* TODO:
 			 * we assume conversion between pointers
 			 * do not need any operation, but due to
diff --git a/types.c b/types.c
@@ -13,6 +13,10 @@ Type
 		.op = VOID,
 		.letter = 'W'
 	},
+	*pvoidtype = &(Type) {
+		.op = PTR,
+		.letter = 'R'
+	},
 	*booltype = &(Type) {
 		.op = INT,
 		.letter = 'B',
@@ -139,6 +143,8 @@ mktype(Type *tp, uint8_t op,
 	register Type *bp;
 	char letter;
 
+	if (op == PTR && tp == voidtype)
+		return pvoidtype;
 	t = (op  ^  (uint8_t) ((unsigned short) tp >> 3))
 	         & NR_TYPE_HASH-1;
 	tbl = &typetab[t];