From 421c7918dc29fb825c16e6eb4095f1d502c7cd92 Mon Sep 17 00:00:00 2001
From: Bryant Wong <llvm-commits@xorshift.org>
Date: Fri, 12 Jul 2019 13:09:39 +0000
Subject: [PATCH] [gn] Tag unneeded variable.

When only building targets without assembly parsers (e.g. `llvm_targets_to_build
= ["NVPTX"]`), `all_targets` is empty and causes GN to warn about an
assigned-but-unused variable.

Differential Revision: https://reviews.llvm.org/D31727

llvm-svn: 365897
---
 llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn b/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn
index 582e3eec7bfe6..f09d8a29ef4f0 100644
--- a/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/include/llvm/Config/BUILD.gn
@@ -383,6 +383,9 @@ template("write_target_def_file") {
     foreach(target, all_targets) {
       value = "$value${invoker.value}($target)\n"
     }
+    if (all_targets == []) {
+      not_needed(invoker, [ "value" ])
+    }
     values = [ "${invoker.key}=$value" ]
   }
 }