[clang-tools-extra] [clang-tidy] Add portability-avoid-platform-specific-fundamental-types (PR #146970)

[via cfe-commits]

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@@ -0,0 +1,121 @@
+//===--- AvoidPlatformSpecificFundamentalTypesCheck.cpp - clang-tidy
+//---------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "AvoidPlatformSpecificFundamentalTypesCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::portability {
+
+AvoidPlatformSpecificFundamentalTypesCheck::
+    AvoidPlatformSpecificFundamentalTypesCheck(StringRef Name,
+                                               ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context) {}
+
+void AvoidPlatformSpecificFundamentalTypesCheck::registerMatchers(
+    MatchFinder *Finder) {
+  // Create a matcher for platform-specific fundamental integer types
+  // This should only match direct uses of builtin types, not typedefs
+  auto PlatformSpecificFundamentalType = qualType(allOf(
+      // Must be a builtin type directly (not through typedef)
+      builtinType(),
+      // Only match the specific fundamental integer types we care about
+      anyOf(asString("short"), asString("short int"), asString("signed short"),
+            asString("signed short int"), asString("unsigned short"),
+            asString("unsigned short int"), asString("int"), asString("signed"),
+            asString("signed int"), asString("unsigned"),
+            asString("unsigned int"), asString("long"), asString("long int"),
+            asString("signed long"), asString("signed long int"),
+            asString("unsigned long"), asString("unsigned long int"),
+            asString("long long"), asString("long long int"),
+            asString("signed long long"), asString("signed long long int"),
+            asString("unsigned long long"),
+            asString("unsigned long long int"))));
+
+  // Match variable declarations with platform-specific fundamental integer
+  // types
+  Finder->addMatcher(
+      varDecl(hasType(PlatformSpecificFundamentalType)).bind("var_decl"), this);
+
+  // Match function declarations with platform-specific fundamental integer
+  // return types
+  Finder->addMatcher(
+      functionDecl(returns(PlatformSpecificFundamentalType)).bind("func_decl"),
+      this);
+
+  // Match function parameters with platform-specific fundamental integer types
+  Finder->addMatcher(
+      parmVarDecl(hasType(PlatformSpecificFundamentalType)).bind("param_decl"),
+      this);
+
+  // Match field declarations with platform-specific fundamental integer types
+  Finder->addMatcher(
+      fieldDecl(hasType(PlatformSpecificFundamentalType)).bind("field_decl"),
+      this);
+
+  // Match typedef declarations with platform-specific fundamental underlying
+  // types
+  Finder->addMatcher(
+      typedefDecl(hasUnderlyingType(PlatformSpecificFundamentalType))
+          .bind("typedef_decl"),
+      this);
+
+  // Match type alias declarations with platform-specific fundamental underlying
+  // types
+  Finder->addMatcher(typeAliasDecl(hasType(PlatformSpecificFundamentalType))
+                         .bind("alias_decl"),
+                     this);
+}
+
+void AvoidPlatformSpecificFundamentalTypesCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  SourceLocation Loc;
+  QualType QT;
+
+  if (const auto *VD = Result.Nodes.getNodeAs<VarDecl>("var_decl")) {
+    Loc = VD->getLocation();
+    QT = VD->getType();
+  } else if (const auto *FD =
+                 Result.Nodes.getNodeAs<FunctionDecl>("func_decl")) {
+    Loc = FD->getLocation();
+    QT = FD->getReturnType();
+  } else if (const auto *PD =
+                 Result.Nodes.getNodeAs<ParmVarDecl>("param_decl")) {
+    Loc = PD->getLocation();
+    QT = PD->getType();
+  } else if (const auto *FD = Result.Nodes.getNodeAs<FieldDecl>("field_decl")) {
+    Loc = FD->getLocation();
+    QT = FD->getType();
+  } else if (const auto *TD =
+                 Result.Nodes.getNodeAs<TypedefDecl>("typedef_decl")) {
+    Loc = TD->getLocation();
+    QT = TD->getUnderlyingType();
+  } else if (const auto *AD =
+                 Result.Nodes.getNodeAs<TypeAliasDecl>("alias_decl")) {
+    Loc = AD->getLocation();
+    QT = AD->getUnderlyingType();
+  } else {
+    return;
+  }
+
+  if (Loc.isInvalid() || QT.isNull())
+    return;
+
+  // Get the type name for the diagnostic
+  std::string TypeName = QT.getAsString();
----------------
EugeneZelenko wrote:

```suggestion
  const std::string TypeName = QT.getAsString();
```

https://github.com/llvm/llvm-project/pull/146970