[all-commits] [llvm/llvm-project] 125590: [analyzer] Fix a few size-type inconsistency relat...

[Ding Fei via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 12559064e05a11e8418425de59d8745f0cfb1122
      https://github.com/llvm/llvm-project/commit/12559064e05a11e8418425de59d8745f0cfb1122
  Author: dingfei <fding at feysh.com>
  Date:   2023-09-01 (Fri, 01 Sep 2023)

  Changed paths:
    M clang/include/clang/StaticAnalyzer/Core/PathSensitive/DynamicExtent.h
    M clang/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp
    M clang/lib/StaticAnalyzer/Core/DynamicExtent.cpp
    M clang/test/Analysis/array-bound-v2-constraint-check.c
    M clang/test/Analysis/flexible-array-members.c
    M clang/test/Analysis/memory-model.cpp

  Log Message:
  -----------
  [analyzer] Fix a few size-type inconsistency relating to DynamicExtent

Size-type inconsistency (signedness) causes confusion and even bugs.
For example when signed compared to unsigned the result might not
be expected. Summary of this commit:

Related APIs changes:
1. getDynamicExtent() returns signed version of extent;
2. Add getDynamicElementCountWithOffset() for offset version of element count;
3. getElementExtent() could be 0, add defensive checking for
   getDynamicElementCount(), if element is of zero-length, try
   ConstantArrayType::getSize() as element count;

Related checker changes:
1. ArrayBoundCheckerV2: add testcase for signed <-> unsigned comparison from
   type-inconsistency results by getDynamicExtent()
2. ExprInspection: use more general API to report more results

Fixes https://github.com/llvm/llvm-project/issues/64920

Reviewed By: donat.nagy, steakhal

Differential Revision: https://reviews.llvm.org/D158499