[clang-tidy] modernize-avoid-c-arrays: avoid main function (PR40604)

Summary:
The check should ignore the main function, the program entry point.
It is not possible to use `std::array<>` for the `argv`.
The alternative is to use `char** argv`.

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=40604 | PR40604 ]]

Reviewers: JonasToth, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: xazax.hun, hans, cfe-commits

Tags: #clang-tools-extra, #clang

Differential Revision: https://reviews.llvm.org/D57787

llvm-svn: 353327

1 files changed, 8 insertions, 1 deletions

diff --git a/clang-tools-extra/clang-tidy/modernize/AvoidCArraysCheck.cpp b/clang-tools-extra/clang-tidy/modernize/AvoidCArraysCheck.cpp
index bceda5c2691..e3dffd0698f 100644
--- a/clang-tools-extra/clang-tidy/modernize/AvoidCArraysCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/AvoidCArraysCheck.cpp
@@ -30,6 +30,12 @@ AST_MATCHER(clang::RecordDecl, isExternCContext) {
   return Node.isExternCContext();
 }
 
+AST_MATCHER(clang::ParmVarDecl, isArgvOfMain) {
+  const clang::DeclContext *DC = Node.getDeclContext();
+  const auto *FD = llvm::dyn_cast<clang::FunctionDecl>(DC);
+  return FD ? FD->isMain() : false;
+}
+
 } // namespace
 
 namespace clang {
@@ -43,7 +49,8 @@ void AvoidCArraysCheck::registerMatchers(MatchFinder *Finder) {
 
   Finder->addMatcher(
       typeLoc(hasValidBeginLoc(), hasType(arrayType()),
-              unless(anyOf(hasParent(varDecl(isExternC())),
+              unless(anyOf(hasParent(parmVarDecl(isArgvOfMain())),
+                           hasParent(varDecl(isExternC())),
                            hasParent(fieldDecl(
                                hasParent(recordDecl(isExternCContext())))),
                            hasAncestor(functionDecl(isExternC())))))