llvm-svn: 140648

[analyzer] Refactor PathDiagnosticLocation: Make PathDiagnosticLocation(SourceLocation...) private. Most of the effort here goes to making BugReport refer to a PathDiagnosticLocation instead of FullSourceLocation. 

(Another step closer to the goal of having Diagnostics which can recover from invalid SourceLocations.)

llvm-svn: 140182

[analyzer] Introduce MallocOverflowSecurityChecker, a simple flow-sensitive checker that may be useful for security auditing.  This checker is currently too noisy to be on by default.

llvm-svn: 136804