From 2e0b114fdce1a10b8433438d8e2251cf708a72ec Mon Sep 17 00:00:00 2001
From: Andrew Kelley <superjoe30@gmail.com>
Date: Mon, 17 Apr 2017 19:28:33 -0400
Subject: [PATCH] add compile error for intToPtr with a 0-bit ptr

See #323
---
 src/ir.cpp         | 7 +++++++
 test/run_tests.cpp | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/src/ir.cpp b/src/ir.cpp
index 2159e8472..e22f96fba 100644
--- a/src/ir.cpp
+++ b/src/ir.cpp
@@ -12473,6 +12473,13 @@ static TypeTableEntry *ir_analyze_instruction_int_to_ptr(IrAnalyze *ira, IrInstr
         return ira->codegen->builtin_types.entry_invalid;
     }
 
+    type_ensure_zero_bits_known(ira->codegen, dest_type);
+    if (!type_has_bits(dest_type)) {
+        ir_add_error(ira, dest_type_value,
+                buf_sprintf("type '%s' has 0 bits and cannot store information", buf_ptr(&dest_type->name)));
+        return ira->codegen->builtin_types.entry_invalid;
+    }
+
     IrInstruction *target = instruction->target->other;
     if (type_is_invalid(target->value.type))
         return ira->codegen->builtin_types.entry_invalid;
diff --git a/test/run_tests.cpp b/test/run_tests.cpp
index 1a5b309a1..c50996634 100644
--- a/test/run_tests.cpp
+++ b/test/run_tests.cpp
@@ -1895,6 +1895,13 @@ export fn entry() {
     const foo = Arch.x86;
 }
     )SOURCE", 1, ".tmp_source.zig:3:21: error: container 'Arch' has no member called 'x86'");
+
+    add_compile_fail_case("int to ptr of 0 bits", R"SOURCE(
+export fn foo() {
+    var x: usize = 0x1000;
+    var y: &void = @intToPtr(&void, x);
+}
+    )SOURCE", 1, ".tmp_source.zig:4:31: error: type '&void' has 0 bits and cannot store information");
 }
 
 //////////////////////////////////////////////////////////////////////////////