Use lexing mode based on FormatStyle.Standard.

Summary:
Some valid pre-C++11 constructs change meaning when lexed in C++11
mode, e.g.
#define x(_a) printf("foo"_a);
(example from http://llvm.org/bugs/show_bug.cgi?id=16342). "foo"_a is treated as
a user-defined string literal when parsed in C++11 mode.
In order to deal with this correctly, we need to set lexing mode according to
which standard the code conforms to. We already have a configuration value for
this (FormatStyle.Standard), which seems to be appropriate to use in this case
as well.

Reviewers: klimek

CC: cfe-commits, gribozavr

Differential Revision: http://llvm-reviews.chandlerc.com/D1028

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@185149 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 3 deletions

diff --git a/tools/clang-format/ClangFormat.cpp b/tools/clang-format/ClangFormat.cpp
index 764200308d..33b7be9f1e 100644
--- a/tools/clang-format/ClangFormat.cpp
+++ b/tools/clang-format/ClangFormat.cpp
@@ -163,7 +163,6 @@ static bool format(std::string FileName) {
     return true;
   }
   FileID ID = createInMemoryFile(FileName, Code.get(), Sources, Files);
-  Lexer Lex(ID, Sources.getBuffer(ID), Sources, getFormattingLangOpts());
   if (Offsets.empty())
     Offsets.push_back(0);
   if (Offsets.size() != Lengths.size() &&
@@ -195,8 +194,10 @@ static bool format(std::string FileName) {
     }
     Ranges.push_back(CharSourceRange::getCharRange(Start, End));
   }
-  tooling::Replacements Replaces =
-      reformat(getStyle(Style, FileName), Lex, Sources, Ranges);
+  FormatStyle FormatStyle = getStyle(Style, FileName);
+  Lexer Lex(ID, Sources.getBuffer(ID), Sources,
+            getFormattingLangOpts(FormatStyle.Standard));
+  tooling::Replacements Replaces = reformat(FormatStyle, Lex, Sources, Ranges);
   if (OutputXML) {
     llvm::outs()
         << "<?xml version='1.0'?>\n<replacements xml:space='preserve'>\n";