From 4d2d04e9fb136e5f9530f4aa298f31e4c40c5ada Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sun, 18 Jan 2009 21:18:58 +0000
Subject: [PATCH] fix rdar://6505352 - Bogus warning with -WUndef, a case
Anders noticed.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62472 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Lex/PPExpressions.cpp | 3 ++-
test/Preprocessor/expr_liveness.c | 8 +++++++-
2 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/lib/Lex/PPExpressions.cpp b/lib/Lex/PPExpressions.cpp
index 168c9d08adf..86f93e407a4 100644
--- a/lib/Lex/PPExpressions.cpp
+++ b/lib/Lex/PPExpressions.cpp
@@ -91,7 +91,8 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
// into a simple 0, unless it is the C++ keyword "true", in which case it
// turns into "1".
if (II->getPPKeywordID() != tok::pp_defined) {
- PP.Diag(PeekTok, diag::warn_pp_undef_identifier) << II;
+ if (ValueLive)
+ PP.Diag(PeekTok, diag::warn_pp_undef_identifier) << II;
Result.Val = II->getTokenID() == tok::kw_true;
Result.Val.setIsUnsigned(false); // "0" is signed intmax_t 0.
Result.setRange(PeekTok.getLocation());
diff --git a/test/Preprocessor/expr_liveness.c b/test/Preprocessor/expr_liveness.c
index 3f4003ea3af..d9e5d7cb25f 100644
--- a/test/Preprocessor/expr_liveness.c
+++ b/test/Preprocessor/expr_liveness.c
@@ -1,4 +1,4 @@
-/* RUN: clang -E %s -DNO_ERRORS &&
+/* RUN: clang -E %s -DNO_ERRORS -Werror -Wundef &&
RUN: not clang -E %s
*/
@@ -44,3 +44,9 @@ baz
#endif
+
+// rdar://6505352
+// -Wundef should not warn about use of undefined identifier if not live.
+#if (!defined(XXX) || XXX > 42)
+#endif
+
--
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