vcc: Promote error checks to assertions

Introduced by eabe58bc but soon after
made obsolete by 9b1f1d17.

lib/libvcc/vcc_acl.c

@@ -477,7 +477,6 @@ vcc_acl_emit_tokens(const struct vcc *tl, const struct acl_e *ae)
 		if (t == ae->t_mask)
 			break;
 		t = vcc_PeekTokenFrom(tl, t);
-		ERRCHK(tl);
 		AN(t);
 		sep = " ";
 	} while (ae->t_mask != NULL);

lib/libvcc/vcc_expr.c

@@ -739,7 +739,7 @@ vcc_expr5(struct vcc *tl, struct expr **e, vcc_type_t fmt)
 	case ID:
 		t = tl->t;
 		t1 = vcc_PeekToken(tl);
-		ERRCHK(tl);
+		AN(t1);
 		sym = VCC_SymbolGet(tl, SYM_MAIN, SYM_NONE,
 		    SYMTAB_PARTIAL_NOERR, XREF_REF);
 		if (sym == NULL && fmt->global_pfx != NULL && t1->tok != '.') {

lib/libvcc/vcc_token.c

@@ -350,15 +350,15 @@ vcc_ExpectVid(struct vcc *tl, const char *what)
 	ERRCHK(tl);
 
 	t2 = vcc_PeekToken(tl);
-	ERRCHK(tl);
+	AN(t2);
 	while (t2->tok == '.') {
 		bad = ".";
 		t2 = vcc_PeekTokenFrom(tl, t2);
-		ERRCHK(tl);
+		AN(t2);
 		if (t2->tok != ID)
 			break;
 		t2 = vcc_PeekTokenFrom(tl, t2);
-		ERRCHK(tl);
+		AN(t2);
 	}
 	if (bad == NULL)
 		bad = VCT_invalid_name(tl->t->b, tl->t->e);

lib/libvcc/vcc_vmod.c

@@ -316,7 +316,7 @@ vcc_ParseImport(struct vcc *tl)
 	ExpectErr(tl, ID);		/* "vmod_name" */
 	mod = tl->t;
 	tmod = vcc_PeekTokenFrom(tl, mod);
-	ERRCHK(tl);
+	AN(tmod);
 	if (tmod->tok == ID && vcc_IdIs(tmod, "as")) {
 		vcc_NextToken(tl);		/* "vmod_name" */
 		vcc_NextToken(tl);		/* "as" */

lib/libvcc/vcc_xref.c

@@ -124,7 +124,7 @@ vcc_AddUses(struct vcc *tl, const struct token *t1, const struct token *t2,
 	pu->t2 = t2;
 	if (pu->t2 == NULL) {
 		pu->t2 = vcc_PeekTokenFrom(tl, t1);
-		ERRCHK(tl);
+		AN(pu->t2);
 	}
 	pu->sym = sym;
 	pu->use = use;