Fix for gcc 4.5.1 warning:

PCHReader.cpp: In member function 'clang::SourceRange clang::PCHReader::ReadSourceRange(const clang::PCHReader::RecordData&, unsigned int&)':
PCHReader.cpp:2946:71: warning: operation on 'Idx' may be undefined

Here, gcc is right, since the order in which arguments to functions are
evaluated is undefined.  It looks like the assumption was left-to-right,
so make that explicit.


Index: tools/clang/lib/Frontend/PCHReader.cpp
===================================================================
--- tools/clang/lib/Frontend/PCHReader.cpp	(revision 105267)
+++ tools/clang/lib/Frontend/PCHReader.cpp	(working copy)
@@ -2942,8 +2942,9 @@ PCHReader::ReadNestedNameSpecifier(const RecordDat
 
 SourceRange
 PCHReader::ReadSourceRange(const RecordData &Record, unsigned &Idx) {
-  return SourceRange(SourceLocation::getFromRawEncoding(Record[Idx++]),
-                     SourceLocation::getFromRawEncoding(Record[Idx++]));
+  SourceLocation beg = SourceLocation::getFromRawEncoding(Record[Idx++]);
+  SourceLocation end = SourceLocation::getFromRawEncoding(Record[Idx++]);
+  return SourceRange(beg, end);
 }
 
 /// \brief Read an integral value
