From 40ff35948625e47964d2adbc3bdec8bd6a40d2db Mon Sep 17 00:00:00 2001
From: Layne Gustafson <lgustaf1@binghamton.edu>
Date: Wed, 15 Jan 2020 17:51:06 -0500
Subject: [PATCH] Only enable requested features

---
 src-self-hosted/stage1.zig | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src-self-hosted/stage1.zig b/src-self-hosted/stage1.zig
index 5d460f1f98..1d08616ae2 100644
--- a/src-self-hosted/stage1.zig
+++ b/src-self-hosted/stage1.zig
@@ -667,6 +667,14 @@ const Stage2TargetDetails = struct {
         var llvm_features_buffer = try std.Buffer.initSize(allocator, 0);
         defer llvm_features_buffer.deinit();
 
+        // First, disable all features.
+        // This way, we only get the ones the user requests.
+        for (std.target.getFeaturesForArch(arch)) |feature| {
+            try llvm_features_buffer.append("-");
+            try llvm_features_buffer.append(feature.llvm_name);
+            try llvm_features_buffer.append(",");
+        }
+
         for (features) |feature| {
             try llvm_features_buffer.append("+");
             try llvm_features_buffer.append(feature.llvm_name);