From 6c7e78746e059916892f1df279b681d962a70954 Mon Sep 17 00:00:00 2001
From: Hans Wennborg <hans@hanshq.net>
Date: Mon, 22 Jul 2013 16:18:13 +0000
Subject: [PATCH] Option parsing: allow aliases in groups

Option aliases in option groups were previously disallowed by an assert.
As far as I can tell, there was no technical reason for this, and I would
like to be able to put cl.exe compatible options in their own group for Clang,
so let's change the assert.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186838 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Option/Option.cpp                  | 10 ++++------
 unittests/Option/OptionParsingTest.cpp |  9 +++++++++
 unittests/Option/Opts.td               |  3 +++
 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/lib/Option/Option.cpp b/lib/Option/Option.cpp
index f1b7941e498..bed779ad554 100644
--- a/lib/Option/Option.cpp
+++ b/lib/Option/Option.cpp
@@ -22,12 +22,10 @@ using namespace llvm::opt;
 Option::Option(const OptTable::Info *info, const OptTable *owner)
   : Info(info), Owner(owner) {
 
-  // Multi-level aliases are not supported, and alias options cannot
-  // have groups. This just simplifies option tracking, it is not an
-  // inherent limitation.
-  assert((!Info || !getAlias().isValid() || (!getAlias().getAlias().isValid() &&
-         !getGroup().isValid())) &&
-         "Multi-level aliases and aliases with groups are unsupported.");
+  // Multi-level aliases are not supported. This just simplifies option
+  // tracking, it is not an inherent limitation.
+  assert(!Info || !getAlias().isValid() || !getAlias().getAlias().isValid() &&
+         "Multi-level aliases are not supported.");
 }
 
 Option::~Option() {
diff --git a/unittests/Option/OptionParsingTest.cpp b/unittests/Option/OptionParsingTest.cpp
index 8bfa99b5de4..2c4fdcfa2c7 100644
--- a/unittests/Option/OptionParsingTest.cpp
+++ b/unittests/Option/OptionParsingTest.cpp
@@ -136,3 +136,12 @@ TEST(Option, ParseWithFlagExclusions) {
   EXPECT_EQ(AL->getLastArgValue(OPT_SLASH_C), "foo");
   EXPECT_EQ(AL->getLastArgValue(OPT_C), "bar");
 }
+
+TEST(Option, ParseAliasInGroup) {
+  TestOptTable T;
+  unsigned MAI, MAC;
+
+  const char *MyArgs[] = { "-I" };
+  OwningPtr<InputArgList> AL(T.ParseArgs(MyArgs, array_endof(MyArgs), MAI, MAC));
+  EXPECT_TRUE(AL->hasArg(OPT_H));
+}
diff --git a/unittests/Option/Opts.td b/unittests/Option/Opts.td
index ccb377fc7e5..8e33ba8580b 100644
--- a/unittests/Option/Opts.td
+++ b/unittests/Option/Opts.td
@@ -16,3 +16,6 @@ def G : JoinedAndSeparate<["-"], "G">, HelpText<"The G option">, MetaVarName<"G"
 def Ceq : Joined<["-", "--"], "C=">, Alias<C>, Flags<[OptFlag1]>;
 
 def H : Flag<["-"], "H">, Flags<[HelpHidden]>;
+
+def my_group : OptionGroup<"my group">;
+def I : Flag<["-"], "I">, Alias<H>, Group<my_group>;