fix some minor bugs in type checking

diff --git a/sem.c b/sem.c
index 181ea84..59e6339 100644 (file)
--- a/sem.c
+++ b/sem.c
@@ -25,6 +25,9 @@ struct ast *sem(struct ast *ast)
        //Check whether all globals are constant
        sem_check_constant(ast);
 
+       // Move all vardecls to the top of the function
+       sem_check_vardecls(ast);
+
        // Check that all functions return and mark void
        sem_check_return(ast);
 
@@ -34,8 +37,5 @@ struct ast *sem(struct ast *ast)
        // Check that a main function exists with the correct type
        sem_check_main(ast);
 
-       // Move all vardecls to the top of the function
-       sem_check_vardecls(ast);
-
        return ast;
 }

diff --git a/sem/hm.c b/sem/hm.c
index 097010d..7e85878 100644 (file)
--- a/sem/hm.c
+++ b/sem/hm.c
@@ -68,7 +68,7 @@ static struct subst *infer_binop(struct gamma *gamma, struct expr *l, struct exp
        struct type *a1, struct type *a2, struct type *rt, struct type *sigma)
 {
        struct subst *s1 = infer_expr(gamma, l, a1);
-       struct subst *s2 = infer_expr(subst_apply_g(s1, gamma), r, a2);
+       struct subst *s2 = infer_expr(subst_apply_g(s1, gamma), r, subst_apply_t(s1, a2));
        struct subst *s3 = subst_union(s2, s1);
        struct subst *s4 = unify(l->loc, subst_apply_t(s3, sigma), rt);
        return subst_union(s4, s3);
@@ -78,7 +78,7 @@ static struct subst *infer_unop(struct gamma *gamma, struct expr *e,
        struct type *a, struct type  *rt, struct type *sigma)
 {
        struct subst *s1 = infer_expr(gamma, e, a);
-       struct subst *s2 = unify(e->loc, subst_apply_t(s1, sigma), rt);
+       struct subst *s2 = unify(e->loc, subst_apply_t(s1, sigma), subst_apply_t(s1, rt));
        return subst_union(s2, s1);
 }
 
@@ -298,7 +298,10 @@ struct subst *infer_stmt(struct gamma *gamma, struct stmt *stmt, struct type *ty
                return s0;
        case svardecl:
                f1 = gamma_fresh(gamma);
-               s0 = infer_expr(gamma, stmt->data.svardecl->expr, f1);
+               if (stmt->data.svardecl->expr != NULL)
+                       s0 = infer_expr(gamma, stmt->data.svardecl->expr, f1);
+               else
+                       s0 = subst_id();
                if (stmt->data.svardecl->type != NULL) {
                        s1 = unify(stmt->loc, f1, stmt->data.svardecl->type);
                        type_free(f1);

diff --git a/sem/type.c b/sem/type.c
index 5e04324..e540d5f 100644 (file)
--- a/sem/type.c
+++ b/sem/type.c
@@ -107,6 +107,7 @@ static struct vardecl *type_vardecl(struct gamma *gamma, struct vardecl *vardecl
        vardecl->type = subst_apply_t(s, t);
        gamma_insert(gamma, ident_str(vardecl->ident), scheme_create(vardecl->type));
 
+       patch_overload_expr(s, vardecl->expr);
        subst_free(s);
 
        return vardecl;