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

[JJ Marr via cfe-commits]

================
@@ -1,75 +1,183 @@
-// RUN: %check_clang_tidy -std=c++11-or-later %s \
+// RUN: %check_clang_tidy -std=c++20-or-later %s \
 // RUN: portability-avoid-platform-specific-fundamental-types %t -- \
 // RUN: -config="{CheckOptions: \
 // RUN: [{key: portability-avoid-platform-specific-fundamental-types.WarnOnInts, \
 // RUN: value: false}, \
 // RUN: {key: portability-avoid-platform-specific-fundamental-types.WarnOnFloats, \
 // RUN: value: false}]}"
 
+// Mock byte
+// NOLINTBEGIN(portability-avoid-platform-specific-fundamental-types)
+namespace std {
+enum class byte : unsigned char {};
+}
+// NOLINTEND(portability-avoid-platform-specific-fundamental-types)
+
 // Test character types that should trigger warnings when WarnOnChars is enabled
 char global_char = 'a';
-// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 signed char global_signed_char = 'b';
-// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 unsigned char global_unsigned_char = 'c';
-// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 // Function parameters
 void func_with_char_param(char param) {}
-// CHECK-MESSAGES: :[[@LINE-1]]:32: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:27: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 void func_with_signed_char_param(signed char param) {}
-// CHECK-MESSAGES: :[[@LINE-1]]:46: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:34: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 void func_with_unsigned_char_param(unsigned char param) {}
-// CHECK-MESSAGES: :[[@LINE-1]]:50: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:36: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 // Function return types
 char func_returning_char() { return 'a'; }
-// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 signed char func_returning_signed_char() { return 'b'; }
-// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 unsigned char func_returning_unsigned_char() { return 'c'; }
-// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 // Struct fields
 struct TestStruct {
   char field_char;
-  // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
   
   signed char field_signed_char;
-  // CHECK-MESSAGES: :[[@LINE-1]]:15: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
   
   unsigned char field_unsigned_char;
-  // CHECK-MESSAGES: :[[@LINE-1]]:17: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 };
 
 // Typedefs
 typedef char char_typedef;
-// CHECK-MESSAGES: :[[@LINE-1]]:14: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 typedef signed char signed_char_typedef;
-// CHECK-MESSAGES: :[[@LINE-1]]:21: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 typedef unsigned char unsigned_char_typedef;
-// CHECK-MESSAGES: :[[@LINE-1]]:23: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 // Type aliases (C++11)
 using char_alias = char;
-// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:20: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 using signed_char_alias = signed char;
-// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:27: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
 
 using unsigned_char_alias = unsigned char;
-// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+// CHECK-MESSAGES: :[[@LINE-1]]:29: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+// Test const and reference parameters
+void func_const_char_ref_param(const char &param) {}
+// CHECK-MESSAGES: :[[@LINE-1]]:38: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+void func_const_signed_char_ref_param(const signed char &param) {}
+// CHECK-MESSAGES: :[[@LINE-1]]:45: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+void func_const_unsigned_char_ref_param(const unsigned char &param) {}
+// CHECK-MESSAGES: :[[@LINE-1]]:47: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+// Test template declarations
+template <typename T> struct TemplateStruct {
+  typedef char char_type;
+  // CHECK-MESSAGES: :[[@LINE-1]]:11: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  
+  char template_field;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  
+  char create_char() { return char('x'); }
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  // CHECK-MESSAGES: :[[@LINE-2]]:31: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+};
+
+// Test namespace usage
+namespace ns_chars {
+  char ns_char;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+}
+
+void test_comprehensive_cases() {
+  // Test with spacing
+  char  spaced_char;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  
+  signed   char   spaced_signed_char;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'signed char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+  // Test pointers
+  char *char_ptr;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  
+  unsigned char *unsigned_char_ptr;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: avoid using platform-dependent character type 'unsigned char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+  // Test static declarations
+  static char static_char;
+  // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+  // Test cv-qualifiers
+  const char const_char = 'a';
+  // CHECK-MESSAGES: :[[@LINE-1]]:9: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  
+  volatile char volatile_char;
+  // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+  
+  const volatile char const_volatile_char = '\0';
+  // CHECK-MESSAGES: :[[@LINE-1]]:18: warning: avoid using platform-dependent character type 'char'; consider using 'char8_t' for text or 'std::byte' for bytes [portability-avoid-platform-specific-fundamental-types]
+
+  // Test auto with initializer
----------------
jj-marr wrote:

I don't want to lint for automatic deduction to `char`.

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