From 5bcd0a0b5030487613bee37ed38945e42c4e6b85 Mon Sep 17 00:00:00 2001
From: Ariel Ben-Yehuda <ariel.byd@gmail.com>
Date: Wed, 15 Oct 2014 20:26:43 +0300
Subject: [PATCH] prevent the creation of integers too big for the target
 architecture

---
 src/librustc/middle/trans/adt.rs    |  4 ++--
 src/librustc/middle/trans/common.rs | 23 ++++++++++++++++++++---
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/src/librustc/middle/trans/adt.rs b/src/librustc/middle/trans/adt.rs
index 66d4b3d804a..861ed01aa3b 100644
--- a/src/librustc/middle/trans/adt.rs
+++ b/src/librustc/middle/trans/adt.rs
@@ -478,7 +478,7 @@ fn ensure_struct_fits_in_address_space(ccx: &CrateContext,
         offset += machine::llsize_of_alloc(ccx, llty);
 
         // We can get away with checking for overflow once per iteration,
-        // because field sizes are less than 1<<60.
+        // because field sizes are less than 1<<61.
         if offset >= ccx.max_obj_size() {
             ccx.report_overbig_object(scapegoat);
         }
@@ -498,7 +498,7 @@ fn ensure_enum_fits_in_address_space(ccx: &CrateContext,
     let discr_size = machine::llsize_of_alloc(ccx, ll_inttype(ccx, discr));
     let (field_size, field_align) = union_size_and_align(fields);
 
-    // This can't overflow because field_size, discr_size, field_align < 1<<60
+    // This can't overflow because field_size, discr_size, field_align < 1<<61
     let total_size = roundup(discr_size, field_align) + field_size;
 
     if total_size >= ccx.max_obj_size() {
diff --git a/src/librustc/middle/trans/common.rs b/src/librustc/middle/trans/common.rs
index a4eb540174f..38a99f16ed6 100644
--- a/src/librustc/middle/trans/common.rs
+++ b/src/librustc/middle/trans/common.rs
@@ -596,17 +596,34 @@ pub fn C_u64(ccx: &CrateContext, i: u64) -> ValueRef {
 }
 
 pub fn C_int<I: AsI64>(ccx: &CrateContext, i: I) -> ValueRef {
-    C_integral(ccx.int_type(), i.as_i64() as u64, true)
+    let v = i.as_i64();
+
+    match machine::llbitsize_of_real(ccx.int_type()) {
+        32 => assert!(v < (1<<31) && v >= -(1<<31)),
+        64 => {},
+        n => fail!("unsupported target size: {}", n)
+    }
+
+    C_integral(ccx.int_type(), v as u64, true)
 }
 
 pub fn C_uint<I: AsU64>(ccx: &CrateContext, i: I) -> ValueRef {
-    C_integral(ccx.int_type(), i.as_u64(), false)
+    let v = i.as_u64();
+
+    match machine::llbitsize_of_real(ccx.int_type()) {
+        32 => assert!(v < (1<<32)),
+        64 => {},
+        n => fail!("unsupported target size: {}", n)
+    }
+
+    C_integral(ccx.int_type(), v, false)
 }
 
 pub trait AsI64 { fn as_i64(self) -> i64; }
 pub trait AsU64 { fn as_u64(self) -> u64; }
 
-// FIXME: remove the intptr conversions
+// FIXME: remove the intptr conversions, because they
+// are host-architecture-dependent
 impl AsI64 for i64 { fn as_i64(self) -> i64 { self as i64 }}
 impl AsI64 for i32 { fn as_i64(self) -> i64 { self as i64 }}
 impl AsI64 for int { fn as_i64(self) -> i64 { self as i64 }}