[clang-tools-extra] 9343ec8 - [clang-tidy] Adding the missing handling of "noreturn" attributes for Obj-C nodes in `InfiniteLoopChecker`

[via cfe-commits]

Author: ziqingluo-90
Date: 2022-08-26T12:44:59-07:00
New Revision: 9343ec861a2e47f05b3b4339f45f6e755b1c5f96

URL: https://github.com/llvm/llvm-project/commit/9343ec861a2e47f05b3b4339f45f6e755b1c5f96
DIFF: https://github.com/llvm/llvm-project/commit/9343ec861a2e47f05b3b4339f45f6e755b1c5f96.diff

LOG: [clang-tidy] Adding the missing handling of "noreturn" attributes for Obj-C nodes in `InfiniteLoopChecker`

With this commit, the `InfiniteLoopChecker` now recognizes message
expressions to "noreturn" methods as well as calls to "noreturn"
blocks.

Reviewed by NoQ, njames93
Differential Revision: https://reviews.llvm.org/D128314

Added: 
    clang-tools-extra/test/clang-tidy/checkers/bugprone/infinite-loop-noreturn.mm

Modified: 
    clang-tools-extra/clang-tidy/bugprone/InfiniteLoopCheck.cpp

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/clang-tidy/bugprone/InfiniteLoopCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/InfiniteLoopCheck.cpp
index 8815de220882e..e2401ff7ec0c0 100644
--- a/clang-tools-extra/clang-tidy/bugprone/InfiniteLoopCheck.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/InfiniteLoopCheck.cpp
@@ -16,15 +16,35 @@ using namespace clang::ast_matchers;
 using clang::tidy::utils::hasPtrOrReferenceInFunc;
 
 namespace clang {
+namespace ast_matchers {
+/// matches a Decl if it has a  "no return" attribute of any kind
+AST_MATCHER(Decl, declHasNoReturnAttr) {
+  return Node.hasAttr<NoReturnAttr>() || Node.hasAttr<CXX11NoReturnAttr>() ||
+         Node.hasAttr<C11NoReturnAttr>();
+}
+
+/// matches a FunctionType if the type includes the GNU no return attribute
+AST_MATCHER(FunctionType, typeHasNoReturnAttr) {
+  return Node.getNoReturnAttr();
+}
+} // namespace ast_matchers
 namespace tidy {
 namespace bugprone {
 
 static internal::Matcher<Stmt>
 loopEndingStmt(internal::Matcher<Stmt> Internal) {
-  // FIXME: Cover noreturn ObjC methods (and blocks?).
+  internal::Matcher<QualType> isNoReturnFunType =
+      ignoringParens(functionType(typeHasNoReturnAttr()));
+  internal::Matcher<Decl> isNoReturnDecl =
+      anyOf(declHasNoReturnAttr(), functionDecl(hasType(isNoReturnFunType)),
+            varDecl(hasType(blockPointerType(pointee(isNoReturnFunType)))));
+
   return stmt(anyOf(
       mapAnyOf(breakStmt, returnStmt, gotoStmt, cxxThrowExpr).with(Internal),
-      callExpr(Internal, callee(functionDecl(isNoReturn())))));
+      callExpr(Internal,
+               callee(mapAnyOf(functionDecl, /* block callee */ varDecl)
+                          .with(isNoReturnDecl))),
+      objcMessageExpr(Internal, callee(isNoReturnDecl))));
 }
 
 /// Return whether `Var` was changed in `LoopStmt`.

diff  --git a/clang-tools-extra/test/clang-tidy/checkers/bugprone/infinite-loop-noreturn.mm b/clang-tools-extra/test/clang-tidy/checkers/bugprone/infinite-loop-noreturn.mm
new file mode 100644
index 0000000000000..142332d33338c
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/bugprone/infinite-loop-noreturn.mm
@@ -0,0 +1,62 @@
+// RUN: %check_clang_tidy %s bugprone-infinite-loop %t -- -- -fblocks -fexceptions
+// RUN: %check_clang_tidy %s bugprone-infinite-loop %t -- -- -fblocks -fobjc-arc -fexceptions
+
+ at interface I
++ (void)foo;
++ (void)bar;
++ (void)baz __attribute__((noreturn));
++ (instancetype)alloc;
+- (instancetype)init;
+ at end
+
+_Noreturn void term();
+
+void plainCFunction() {
+  int i = 0;
+  int j = 0;
+  int a[10];
+
+  while (i < 10) {
+    // no warning, function term has C noreturn attribute
+    term();
+  }
+  while (i < 10) {
+    // no warning, class method baz has noreturn attribute
+    [I baz];
+  }
+  while (i + j < 10) {
+    // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this loop is infinite; none of its condition variables (i, j) are updated in the loop body [bugprone-infinite-loop]
+    [I foo];
+  }
+  while (i + j < 10) {
+    [I foo];
+    [I baz]; // no warning, class method baz has noreturn attribute
+  }
+
+  void (^block)() = ^{
+  };
+  void __attribute__((noreturn)) (^block_nr)(void) = ^void __attribute__((noreturn)) (void) { throw "err"; };
+
+  while (i < 10) {
+    // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this loop is infinite; none of its condition variables (i) are updated in the loop body [bugprone-infinite-loop]
+    block();
+  }
+  while (i < 10) {
+    // no warning, the block has "noreturn" arribute
+    block_nr();
+  }
+}
+
+ at implementation I
++ (void)bar {
+}
+
++ (void)foo {
+  static int i = 0;
+
+  while (i < 10) {
+    // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this loop is infinite; none of its condition variables (i) are updated in the loop body [bugprone-infinite-loop]
+    [I bar];
+  }
+}
+ at end