*** Bug 10683 has been marked as a duplicate of this bug. ***

It has nothing to do with MFC though. Any file containing "//\" with an empty line afterwards will cause a crash.

This code:
  // \  
int a; //dead line

Will be preprocessed as:
 // int a; //dead line

Thus the second line is lost.

Fixed in r147091.

The bug is active in clang 3.6.2. This code:

int main(int argc, char* argv[]) {
	// \
	int a; //dead line
	int b;
	return 0;
}

is preprocessed as:

int main(int argc, char* argv[]) {


	int b;
	return 0;
}