Author: Ben Shi Date: 2023-12-30T14:49:42+08:00 New Revision: 925ff9e1a218720cd61bd7c9f5f85ded4ecbf9a1
URL: https://github.com/llvm/llvm-project/commit/925ff9e1a218720cd61bd7c9f5f85ded4ecbf9a1 DIFF: https://github.com/llvm/llvm-project/commit/925ff9e1a218720cd61bd7c9f5f85ded4ecbf9a1.diff LOG: [clang][analyzer] Support 'fflush' in the StdLibraryFunctionsChecker (#76557) Co-authored-by: Balazs Benics <benicsbal...@gmail.com> Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp clang/test/Analysis/stream-errno.c Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 3c08d1808b0e7f..2d5391702385a7 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -1126,9 +1126,11 @@ Improvements ^^^^^^^^^^^^ - Improved the ``unix.StdCLibraryFunctions`` checker by modeling more - functions like ``send``, ``recv``, ``readlink`` and ``errno`` behavior. + functions like ``send``, ``recv``, ``readlink``, ``fflush`` and + ``errno`` behavior. (`52ac71f92d38 <https://github.com/llvm/llvm-project/commit/52ac71f92d38f75df5cb88e9c090ac5fd5a71548>`_, `#71373 <https://github.com/llvm/llvm-project/pull/71373>`_, + `#76557 <https://github.com/llvm/llvm-project/pull/76557>`_, `#71392 <https://github.com/llvm/llvm-project/pull/71392>`_) - Fixed a false negative for when accessing a nonnull property (ObjC). diff --git a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp index fffcaf7ed18fb7..4ca49b9c0546d9 100644 --- a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp +++ b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp @@ -2244,6 +2244,14 @@ void StdLibraryFunctionsChecker::initFunctionSummaries( .ArgConstraint(NotNull(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); + // int fflush(FILE *stream); + addToFunctionSummaryMap( + "fflush", Signature(ArgTypes{FilePtrTy}, RetType{IntTy}), + Summary(NoEvalCall) + .Case(ReturnsZero, ErrnoMustNotBeChecked, GenericSuccessMsg) + .Case({ReturnValueCondition(WithinRange, SingleValue(EOFv))}, + ErrnoNEZeroIrrelevant, GenericFailureMsg)); + // long ftell(FILE *stream); // From 'The Open Group Base Specifications Issue 7, 2018 edition': // "The ftell() function shall not change the setting of errno if diff --git a/clang/test/Analysis/stream-errno.c b/clang/test/Analysis/stream-errno.c index bf0a61db2424f9..f44ee6070708b2 100644 --- a/clang/test/Analysis/stream-errno.c +++ b/clang/test/Analysis/stream-errno.c @@ -222,3 +222,29 @@ void check_fileno(void) { } if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}} } + +void check_fflush_opened_file(void) { + FILE *F = tmpfile(); + if (!F) + return; + int N = fflush(F); + if (N == EOF) { + clang_analyzer_eval(errno != 0); // expected-warning{{TRUE}} + if (errno) {} // no-warning + } else { + clang_analyzer_eval(N == 0); // expected-warning{{TRUE}} + if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}} + } + fclose(F); +} + +void check_fflush_all(void) { + int N = fflush(NULL); + if (N == 0) { + if (errno) {} // expected-warning{{An undefined value may be read from 'errno'}} + } else { + clang_analyzer_eval(N == EOF); // expected-warning{{TRUE}} + clang_analyzer_eval(errno != 0); // expected-warning{{TRUE}} + if (errno) {} // no-warning + } +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
