From db20190fe449d5e44cae9f8e5ec2fd96b4b9e6f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonathan=20M=C3=BCller?= <git@foonathan.net>
Date: Wed, 12 Apr 2017 14:52:28 +0200
Subject: [PATCH] Workaround clang bug with #undef output

---
 src/libclang/preprocessor.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/libclang/preprocessor.cpp b/src/libclang/preprocessor.cpp
index e5ffd29..1a0b766 100644
--- a/src/libclang/preprocessor.cpp
+++ b/src/libclang/preprocessor.cpp
@@ -475,7 +475,11 @@ namespace
     ts::optional<std::string> parse_undef(position& p)
     {
         // format (at new line): #undef <name>
-        if (!p.was_newl() || !starts_with(p, "#undef"))
+        // due to a clang bug (http://bugs.llvm.org/show_bug.cgi?id=32631) I'll also an undef in the middle of the line
+        // the only issue is with string literals containing `#undef`.
+        // those will be stripped and evaluated
+        // however, this kind of usage should be rare™
+        if (/*!p.was_newl() ||*/ !starts_with(p, "#undef"))
             return ts::nullopt;
         p.skip(std::strlen("#undef"));