From 24b61ac832c79fc1cd2c04437dadca171cda63ed Mon Sep 17 00:00:00 2001
From: Petr Hosek <phosek@chromium.org>
Date: Fri, 18 May 2018 18:33:07 +0000
Subject: [PATCH] [Support] Avoid normalization in sys::getDefaultTargetTriple

The return value of sys::getDefaultTargetTriple, which is derived from
-DLLVM_DEFAULT_TRIPLE, is used to construct tool names, default target,
and in the future also to control the search path directly; as such it
should be used textually, without interpretation by LLVM.

Normalization of this value may lead to unexpected results, for example
if we configure LLVM with -DLLVM_DEFAULT_TARGET_TRIPLE=x86_64-linux-gnu,
normalization will transform that value to x86_64--linux-gnu. Driver will
use that value to search for tools prefixed with x86_64--linux-gnu- which
may be confusing. This is also inconsistent with the behavior of the
--target flag which is taken as-is without any normalization and overrides
the value of LLVM_DEFAULT_TARGET_TRIPLE.

Users of sys::getDefaultTargetTriple already perform their own
normalization as needed, so this change shouldn't impact existing logic.

Differential Revision: https://reviews.llvm.org/D46910

llvm-svn: 332750
---
 clang/lib/Frontend/CompilerInvocation.cpp | 3 ++-
 llvm/cmake/modules/GetHostTriple.cmake    | 8 ++++----
 llvm/lib/Support/Unix/Host.inc            | 2 +-
 llvm/lib/Support/Windows/Host.inc         | 2 +-
 4 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 849e3ba9f277..b1e0d9ab7945 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -2927,10 +2927,11 @@ static void ParseTargetArgs(TargetOptions &Opts, ArgList &Args,
   Opts.FPMath = Args.getLastArgValue(OPT_mfpmath);
   Opts.FeaturesAsWritten = Args.getAllArgValues(OPT_target_feature);
   Opts.LinkerVersion = Args.getLastArgValue(OPT_target_linker_version);
-  Opts.Triple = llvm::Triple::normalize(Args.getLastArgValue(OPT_triple));
+  Opts.Triple = Args.getLastArgValue(OPT_triple);
   // Use the default target triple if unspecified.
   if (Opts.Triple.empty())
     Opts.Triple = llvm::sys::getDefaultTargetTriple();
+  Opts.Triple = llvm::Triple::normalize(Opts.Triple);
   Opts.OpenCLExtensionsAsWritten = Args.getAllArgValues(OPT_cl_ext_EQ);
   Opts.ForceEnableInt128 = Args.hasArg(OPT_fforce_enable_int128);
   Opts.NVPTXUseShortPointers = Args.hasFlag(
diff --git a/llvm/cmake/modules/GetHostTriple.cmake b/llvm/cmake/modules/GetHostTriple.cmake
index 019188a59cc6..7b842450b726 100644
--- a/llvm/cmake/modules/GetHostTriple.cmake
+++ b/llvm/cmake/modules/GetHostTriple.cmake
@@ -4,15 +4,15 @@
 function( get_host_triple var )
   if( MSVC )
     if( CMAKE_SIZEOF_VOID_P EQUAL 8 )
-      set( value "x86_64-pc-win32" )
+      set( value "x86_64-pc-windows-msvc" )
     else()
-      set( value "i686-pc-win32" )
+      set( value "i686-pc-windows-msvc" )
     endif()
   elseif( MINGW AND NOT MSYS )
     if( CMAKE_SIZEOF_VOID_P EQUAL 8 )
-      set( value "x86_64-w64-mingw32" )
+      set( value "x86_64-w64-windows-gnu" )
     else()
-      set( value "i686-pc-mingw32" )
+      set( value "i686-pc-windows-gnu" )
     endif()
   else( MSVC )
     set(config_guess ${LLVM_MAIN_SRC_DIR}/cmake/config.guess)
diff --git a/llvm/lib/Support/Unix/Host.inc b/llvm/lib/Support/Unix/Host.inc
index 5580e63893c6..b65f84bf4444 100644
--- a/llvm/lib/Support/Unix/Host.inc
+++ b/llvm/lib/Support/Unix/Host.inc
@@ -64,5 +64,5 @@ std::string sys::getDefaultTargetTriple() {
     TargetTripleString = EnvTriple;
 #endif
 
-  return Triple::normalize(TargetTripleString);
+  return TargetTripleString;
 }
diff --git a/llvm/lib/Support/Windows/Host.inc b/llvm/lib/Support/Windows/Host.inc
index 90a6fb316703..58c4dc5d678f 100644
--- a/llvm/lib/Support/Windows/Host.inc
+++ b/llvm/lib/Support/Windows/Host.inc
@@ -30,5 +30,5 @@ std::string sys::getDefaultTargetTriple() {
     Triple = EnvTriple;
 #endif
 
-  return Triple::normalize(Triple);
+  return Triple;
 }