From 60a658250ea2ee6dd10425d7070c373262762b1c Mon Sep 17 00:00:00 2001
From: Lindsey Kuper <lindsey@rockstargirl.org>
Date: Wed, 20 Jun 2012 14:33:25 -0700
Subject: [PATCH] Don't force resolution of integral type vars in unary minus
exprs
These were getting resolved too early, when they were still
unconstrained by the rest of the typing context. Waiting a bit longer
to resolve them gives the rest of the typing context a chance to come
into play, so that they don't default to `int`.
---
src/rustc/middle/typeck/check.rs | 9 ++++++++-
src/test/run-pass/integer-literal-suffix-inference.rs | 8 ++++----
2 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/src/rustc/middle/typeck/check.rs b/src/rustc/middle/typeck/check.rs
index 04d3c4f90c5..b126e5c55ff 100644
--- a/src/rustc/middle/typeck/check.rs
+++ b/src/rustc/middle/typeck/check.rs
@@ -1198,7 +1198,14 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
}
}
ast::neg {
- oprnd_t = structurally_resolved_type(fcx, oprnd.span, oprnd_t);
+ // If the operand's type is an integral type variable, we
+ // don't want to resolve it yet, because the rest of the
+ // typing context might not have had the opportunity to
+ // constrain it yet.
+ if !(ty::type_is_var_integral(oprnd_t)) {
+ oprnd_t = structurally_resolved_type(fcx, oprnd.span,
+ oprnd_t);
+ }
if !(ty::type_is_integral(oprnd_t) ||
ty::type_is_fp(oprnd_t)) {
oprnd_t = check_user_unop(fcx, "-", "unary-", expr,
diff --git a/src/test/run-pass/integer-literal-suffix-inference.rs b/src/test/run-pass/integer-literal-suffix-inference.rs
index 8fd51180477..5d157658aa1 100644
--- a/src/test/run-pass/integer-literal-suffix-inference.rs
+++ b/src/test/run-pass/integer-literal-suffix-inference.rs
@@ -16,22 +16,22 @@ fn main() {
let _i: i8 = -128;
let j = -128;
- // id_i8(j);
+ id_i8(j);
id_i8(-128);
let _i: i16 = -32_768;
let j = -32_768;
- // id_i16(j);
+ id_i16(j);
id_i16(-32_768);
let _i: i32 = -2_147_483_648;
let j = -2_147_483_648;
- // id_i32(j);
+ id_i32(j);
id_i32(-2_147_483_648);
let _i: i64 = -9_223_372_036_854_775_808;
let j = -9_223_372_036_854_775_808;
- // id_i64(j);
+ id_i64(j);
id_i64(-9_223_372_036_854_775_808);
let _i: uint = 1;