Summary: public
C++ assignment operation result is lvalue, while in C it was rvalue.
This leads to different AST produced by clang for then same code!
Use language information from clang (`-x` flag) to distinguish these cases.
More specifically, let's look at following code:
int r;
int f = (r = 3);
// type of (r = 3) expression:
// C/objC -> int rvalue
// C++/objC++ -> int lvalue
Existing code did extra dereference because it was rvalue in C and there was no cast afterwards
in C++ there will be extra LValueToRvalue cast when neccesary so we don't have to do extra dereference manually
Reference:
http://en.cppreference.com/w/c/language/value_category (search for 'assignment and compound assignment operators')
NOTE: AST output doesn't change when something is hidden behind `extern "C"`, so we should use global language information
Reviewed By: ddino
Differential Revision: D2549866
fb-gh-sync-id: b193b11
Andrzej Kotulski