ref: 5711ab3b30b229b651424f7978bc39f0b044e193
parent: f363110a62803e055334516ba0e1899e62be65ac
author: Ori Bernstein <ori@markovcorp.com>
date: Wed Aug 23 07:46:44 EDT 2017
Check constraints correctly on typarams.
--- a/parse/infer.c
+++ b/parse/infer.c
@@ -33,6 +33,7 @@
static void infernode(Node **np, Type *ret, int *sawret);
static void inferexpr(Node **np, Type *ret, int *sawret);
static void inferdecl(Node *n);
+static int tryconstrain(Type *ty, Trait *tr);
static Type *tf(Type *t);
@@ -165,8 +166,12 @@
Node **args;
char buf[512];
+ if (!n)
+ return strdup("???"); switch (n->type) {- default: s = strdup(nodestr[n->type]); break;
+ default:
+ s = strdup(nodestr[n->type]);
+ break;
case Ndecl:
d = declname(n);
t = nodetystr(n);
@@ -749,13 +754,102 @@
bindtype(e, n->decl.init->expr.type);
}
-/* Constrains a type to implement the required constraints. On
- * type variables, the constraint is added to the required
- * constraint list. Otherwise, the type is checked to see
- * if it has the required constraint */
-static void
-constrain(Node *ctx, Type *base, Trait *tr)
+/* this doesn't walk through named types, so it can't recurse infinitely. */
+int
+tymatchrank(Type *pat, Type *to)
{+ int match, q;
+ size_t i;
+ Ucon *puc, *tuc;
+
+ pat = tysearch(pat);
+ to = tysearch(to);
+ if (pat->type == Typaram) {+ if (!pat->trneed)
+ return 0;
+ for (i = 0; bsiter(pat->trneed, &i); i++)
+ if (!tryconstrain(to, traittab[i]))
+ return -1;
+ return 0;
+ } else if (pat->type == Tyvar) {+ return 1;
+ } else if (pat->type != to->type) {+ return -1;
+ }
+
+ match = 0;
+ switch (pat->type) {+ case Tystruct:
+ if (pat->nmemb != to->nmemb)
+ return -1;
+ for (i = 0; i < pat->nmemb; i++) {+ if (!streq(declname(pat->sdecls[i]),declname( to->sdecls[i])))
+ return -1;
+ q = tymatchrank(decltype(pat->sdecls[i]), decltype(to->sdecls[i]));
+ if (q < 0)
+ return -1;
+ match += q;
+ }
+ break;
+ case Tyunion:
+ if (pat->nmemb != to->nmemb)
+ return -1;
+ for (i = 0; i < pat->nmemb; i++) {+ if (!nameeq(pat->udecls[i], to->udecls[i]))
+ return -1;
+ puc = pat->udecls[i];
+ tuc = to->udecls[i];
+ if (puc->etype && tuc->etype) {+ q = tymatchrank(puc->etype, tuc->etype);
+ if (q < 0)
+ return -1;
+ match += q;
+ } else if (puc->etype != tuc->etype) {+ return -1;
+ }
+ }
+ break;
+ case Tyname:
+ if (!nameeq(pat->name, to->name))
+ return -1;
+ if (pat->narg != to->narg)
+ return -1;
+ for (i = 0; i < pat->narg; i++) {+ q = tymatchrank(pat->arg[i], to->arg[i]);
+ if (q < 0)
+ return -1;
+ match += q;
+ }
+ break;
+ case Tyarray:
+ /* unsized arrays are ok */
+ if (pat->asize && to->asize) {+ if (!!litvaleq(pat->asize->expr.args[0], to->asize->expr.args[0]))
+ return -1;
+ } else if (pat->asize != to->asize) {+ return -1;
+ }
+ else return tymatchrank(pat->sub[0], to->sub[0]);
+ break;
+ default:
+ if (pat->nsub != to->nsub)
+ break;
+ if (pat->type == to->type)
+ match = 1;
+ for (i = 0; i < pat->nsub; i++) {+ q = tymatchrank(pat->sub[i], to->sub[i]);
+ if (q < 0)
+ return -1;
+ match += q;
+ }
+ break;
+ }
+ return match;
+}
+
+static int
+tryconstrain(Type *base, Trait *tr)
+{Traitmap *tm;
Bitset *bs;
Type *ty;
@@ -766,25 +860,25 @@
tm = traitmap->sub[ty->type];
while (1) {if (ty->type == Typaram && bshas(ty->trneed, tr->uid))
- return;
+ return 1;
if (ty->type == Tyvar) {if (!ty->trneed)
ty->trneed = mkbs();
bsput(ty->trneed, tr->uid);
- return;
+ return 1;
}
if (bshas(tm->traits, tr->uid))
- return;
+ return 1;
if (tm->name && ty->type == Tyname) {bs = htget(tm->name, ty->name);
if (bs && bshas(bs, tr->uid))
- return;
+ return 1;
}
for (i = 0; i < tm->nfilter; i++) {if (tm->filtertr[i]->uid != tr->uid)
continue;
if (tymatchrank(tm->filter[i], ty) >= 0)
- return;
+ return 1;
}
if (!tm->sub[ty->type])
break;
@@ -796,7 +890,18 @@
break;
base = base->sub[0];
}
- fatal(ctx, "%s needs trait %s near %s", tystr(ty), namestr(tr->name), ctxstr(ctx));
+ return 0;
+}
+
+/* Constrains a type to implement the required constraints. On
+ * type variables, the constraint is added to the required
+ * constraint list. Otherwise, the type is checked to see
+ * if it has the required constraint */
+static void
+constrain(Node *ctx, Type *base, Trait *tr)
+{+ if (!tryconstrain(base, tr))
+ fatal(ctx, "%s needs trait %s near %s", tystr(base), namestr(tr->name), ctxstr(ctx));
}
static void
--- a/parse/type.c
+++ b/parse/type.c
@@ -851,91 +851,6 @@
return eq;
}
-/* this doesn't walk through named types, so it can't recurse infinitely. */
-int
-tymatchrank(Type *pat, Type *to)
-{- int match, q;
- size_t i;
- Ucon *puc, *tuc;
-
- pat = tysearch(pat);
- to = tysearch(to);
- if (pat->type == Typaram)
- return 0;
- else if (pat->type != to->type)
- return -1;
-
- match = 0;
- switch (pat->type) {- case Tystruct:
- if (pat->nmemb != to->nmemb)
- return -1;
- for (i = 0; i < pat->nmemb; i++) {- if (!streq(declname(pat->sdecls[i]),declname( to->sdecls[i])))
- return -1;
- q = tymatchrank(decltype(pat->sdecls[i]), decltype(to->sdecls[i]));
- if (q < 0)
- return -1;
- match += q;
- }
- break;
- case Tyunion:
- if (pat->nmemb != to->nmemb)
- return -1;
- for (i = 0; i < pat->nmemb; i++) {- if (!nameeq(pat->udecls[i], to->udecls[i]))
- return -1;
- puc = pat->udecls[i];
- tuc = to->udecls[i];
- if (puc->etype && tuc->etype) {- q = tymatchrank(puc->etype, tuc->etype);
- if (q < 0)
- return -1;
- match += q;
- } else if (puc->etype != tuc->etype) {- return -1;
- }
- }
- break;
- case Tyname:
- if (!nameeq(pat->name, to->name))
- return -1;
- if (pat->narg != to->narg)
- return -1;
- for (i = 0; i < pat->narg; i++) {- q = tymatchrank(pat->arg[i], to->arg[i]);
- if (q < 0)
- return -1;
- match += q;
- }
- break;
- case Tyarray:
- /* unsized arrays are ok */
- if (pat->asize && to->asize) {- if (!!litvaleq(pat->asize->expr.args[0], to->asize->expr.args[0]))
- return -1;
- } else if (pat->asize != to->asize) {- return -1;
- }
- else return tymatchrank(pat->sub[0], to->sub[0]);
- break;
- default:
- if (pat->nsub != to->nsub)
- break;
- if (pat->type == to->type)
- match = 1;
- for (i = 0; i < pat->nsub; i++) {- q = tymatchrank(pat->sub[i], to->sub[i]);
- if (q < 0)
- return -1;
- match += q;
- }
- break;
- }
- return match;
-}
-
size_t
tyidfmt(char *buf, size_t sz, Type *ty)
{