[analyzer] Improves the logic of GenericTaintChecker identifying stdin.
Summary:
GenericTaintChecker can't recognize stdin in some cases. The reason is that if (PtrTy->getPointeeType() == C.getASTContext().getFILEType() does not hold when stdin is encountered.
My platform is ubuntu16.04 64bit, gcc 5.4.0, glibc 2.23. The definition of stdin is as follows:
__BEGIN_NAMESPACE_STD /* The opaque type of streams. This is the definition used elsewhere. */ typedef struct _IO_FILE FILE; ___END_NAMESPACE_STD ... /* The opaque type of streams. This is the definition used elsewhere. */ typedef struct _IO_FILE __FILE; ... /* Standard streams. */ extern struct _IO_FILE *stdin; /* Standard input stream. */ extern struct _IO_FILE *stdout; /* Standard output stream. */ extern struct _IO_FILE *stderr; /* Standard error output stream. */
The type of stdin is as follows AST:
ElaboratedType 0xc911170'struct _IO_FILE'sugar `-RecordType 0xc911150'struct _IO_FILE' `-CXXRecord 0xc923ff0'_IO_FILE'
C.getASTContext().GetFILEType() is as follows AST:
TypedefType 0xc932710 'FILE' sugar
|-Typedef 0xc9111c0 'FILE'
`-ElaboratedType 0xc911170 'struct _IO_FILE' sugar
`-RecordType 0xc911150 'struct _IO_FILE'
`-CXXRecord 0xc923ff0 '_IO_FILE'So I think it's better to use getCanonicalType().
Reviewers: zaks.anna, NoQ, george.karpenkov, a.sidorin
Reviewed By: zaks.anna, a.sidorin
Subscribers: a.sidorin, cfe-commits, xazax.hun, szepet, MTC
Differential Revision: https://reviews.llvm.org/D39159
llvm-svn: 326709