From f077c3c4ccd03f48f785ee812ab2c88c85792014 Mon Sep 17 00:00:00 2001
From: LemonBoy <thatlemon@gmail.com>
Date: Fri, 20 Dec 2019 09:44:10 +0100
Subject: [PATCH] Fix comptime evaluation of runtime array access

Fix #3951
---
 src/ir.cpp                        | 1 +
 test/stage1/behavior/pointers.zig | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/src/ir.cpp b/src/ir.cpp
index bc16cef561..0c7160fa80 100644
--- a/src/ir.cpp
+++ b/src/ir.cpp
@@ -19500,6 +19500,7 @@ static IrInstruction *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstruct
         }
 
         if (orig_array_ptr_val->special != ConstValSpecialRuntime &&
+            orig_array_ptr_val->data.x_ptr.special != ConstPtrSpecialHardCodedAddr &&
             (orig_array_ptr_val->data.x_ptr.mut != ConstPtrMutRuntimeVar ||
                 array_type->id == ZigTypeIdArray))
         {
diff --git a/test/stage1/behavior/pointers.zig b/test/stage1/behavior/pointers.zig
index 1dd07c8986..e1004243fc 100644
--- a/test/stage1/behavior/pointers.zig
+++ b/test/stage1/behavior/pointers.zig
@@ -282,3 +282,9 @@ test "pointer sentinel with +inf" {
     S.doTheTest();
     comptime S.doTheTest();
 }
+
+test "pointer to array at fixed address" {
+    const array = @intToPtr(*volatile [1]u32, 0x10);
+    // Silly check just to reference `array`
+    expect(@ptrToInt(&array[0]) == 0x10);
+}