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[cc2] Fix wafting switches nodes

We need to have all the nodes related to a switch table
together, because otherwise it is impossible to build
a jump table. The code was wrong and it was generating
corrupted statement lists.

--- a/cc2/parser.c

+++ b/cc2/parser.c

@@ -339,20 +339,36 @@

 	push(np);

 }

+/*

+ * Move np (which is a OCASE/ODEFAULT/OESWITCH) to be contigous with

+ * the last switch table. It is a bit ugly to touch directly curstmt

+ * here, but moving this function to node.c is worse, because we are

+ * putting knowledge of how the text is parsed into the node

+ * represtation module.

+ */

 static void

 waft(Node *np)

 {

-	Node *p;

+	Node *lastcase, *next;;

 	struct swtch *cur;

+	extern Node *curstmt;

 	if (swp == swtbl)

 		error(EWTACKU);

 	cur = swp - 1;

-	p = cur->last;

-	np->next = p->next;

-	np->prev = p;

-	p->next = np;

+	lastcase = cur->last;

+	next = lastcase->next;

+

+	np->next = next;

+	np->prev = lastcase;

+

+	if (next)

+		next->prev = np;

+	lastcase->next = np;

+

+	if (curstmt == cur->last)

+		curstmt = np;

 	cur->last = np;

 	cur->nr++;

 }

@@ -361,13 +377,17 @@

 bswitch(char *token, union tokenop u)

 {

 	struct swtch *cur;

+	Node *np = newnode(u.op);

 	if (swp == &swtbl[NR_BLOCK+1])

 		error(EWTACKO);

 	cur = swp++;

 	cur->nr = 0;

-	jump(token, u);

-	cur->first = cur->last = push(pop());

+

+	eval(strtok(NULL, "\t\n"));

+	np->left = pop();

+

+	push(cur->first = cur->last = np);

 }

 static void

@@ -379,7 +399,7 @@

 		error(EWTACKU);

 	jump(token, u);

 	waft(pop());

-	cur = swp--;

+	cur = --swp;

 	cur->first->u.i = cur->nr;

 }