libcpp: Implement P2362R3 - Remove non-encodable wide character literals and multicharacter [PR106647]

Message ID Ywh3t1fvp+IGEBGa@tucnak
State New, archived
Headers
Series libcpp: Implement P2362R3 - Remove non-encodable wide character literals and multicharacter [PR106647] |

Commit Message

Jakub Jelinek Aug. 26, 2022, 7:35 a.m. UTC
  Hi!

My understanding of the paper is that we just want to promote the CPP_WCHAR
"character constant too long for its type" warning to error as it is already
error for u8, u and U literals.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2022-08-26  Jakub Jelinek  <jakub@redhat.com>

	PR c++/106647
	* charset.cc (wide_str_to_charconst): Implement P2362R3 - Remove
	non-encodable wide character literals and multicharacter.  For
	C++23 use CPP_DL_ERROR instead of CPP_DL_WARNING for
	"character constant too long for its type" diagnostics on CPP_WCHAR
	literals.

	* g++.dg/cpp23/wchar-multi1.C: New test.
	* g++.dg/cpp23/wchar-multi2.C: New test.


	Jakub
  

Comments

Jason Merrill Aug. 26, 2022, 1:59 p.m. UTC | #1
On 8/26/22 03:35, Jakub Jelinek wrote:
> Hi!
> 
> My understanding of the paper is that we just want to promote the CPP_WCHAR
> "character constant too long for its type" warning to error as it is already
> error for u8, u and U literals.
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

OK.

> 2022-08-26  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR c++/106647
> 	* charset.cc (wide_str_to_charconst): Implement P2362R3 - Remove
> 	non-encodable wide character literals and multicharacter.  For
> 	C++23 use CPP_DL_ERROR instead of CPP_DL_WARNING for
> 	"character constant too long for its type" diagnostics on CPP_WCHAR
> 	literals.
> 
> 	* g++.dg/cpp23/wchar-multi1.C: New test.
> 	* g++.dg/cpp23/wchar-multi2.C: New test.
> 
> --- libcpp/charset.cc.jj	2022-08-25 11:54:38.849924475 +0200
> +++ libcpp/charset.cc	2022-08-25 18:36:20.650415220 +0200
> @@ -2170,7 +2170,11 @@ wide_str_to_charconst (cpp_reader *pfile
>        character constant is guaranteed to overflow.  */
>     if (str.len > nbwc * 2)
>       cpp_error (pfile, (CPP_OPTION (pfile, cplusplus)
> -		       && (type == CPP_CHAR16 || type == CPP_CHAR32))
> +		       && (type == CPP_CHAR16
> +			   || type == CPP_CHAR32
> +			   /* In C++23 this is error even for L'ab'.  */
> +			   || (type == CPP_WCHAR
> +			       && CPP_OPTION (pfile, size_t_literals))))
>   		      ? CPP_DL_ERROR : CPP_DL_WARNING,
>   	       "character constant too long for its type");
>   
> --- gcc/testsuite/g++.dg/cpp23/wchar-multi1.C.jj	2022-08-25 18:08:01.973426155 +0200
> +++ gcc/testsuite/g++.dg/cpp23/wchar-multi1.C	2022-08-25 18:51:30.476687112 +0200
> @@ -0,0 +1,42 @@
> +// P2362R3 - Remove non-encodable wide character literals and multicharacter
> +// wide character literals.
> +// { dg-do compile }
> +
> +char a = 'a';
> +int b = 'ab';			// { dg-warning "multi-character character constant" }
> +int c = '\u05D9';		// { dg-warning "multi-character character constant" }
> +#if __SIZEOF_INT__ > 2
> +int d = '\U0001F525';		// { dg-warning "multi-character character constant" "" { target int32 } }
> +#endif
> +int e = 'abcd';			// { dg-warning "multi-character character constant" }
> +wchar_t f = L'f';
> +wchar_t g = L'gh';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> +wchar_t h = L'ijkl';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> +wchar_t i = L'\U0001F525';	// { dg-error "character constant too long for its type" "" { target { c++23 && { ! 4byte_wchar_t } } } }
> +				// { dg-warning "character constant too long for its type" "" { target { c++20_down && { ! 4byte_wchar_t } } } .-1 }
> +#ifdef __cpp_char8_t
> +typedef char8_t u8;
> +#else
> +typedef char u8;
> +#endif
> +#if __cpp_unicode_characters >= 201411
> +u8 j = u8'j';
> +u8 k = u8'kl';			// { dg-error "character constant too long for its type" "" { target c++17 } }
> +u8 l = u8'\U0001F525';		// { dg-error "character constant too long for its type" "" { target c++17 }  }
> +#endif
> +#if __cpp_unicode_characters >= 200704
> +char16_t m = u'm';
> +char16_t n = u'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
> +char16_t o = u'\u05D9';
> +char16_t p = u'\U0001F525';	// { dg-error "character constant too long for its type" "" { target c++11 } }
> +char32_t q = U'm';
> +char32_t r = U'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
> +char32_t s = U'\u05D9';
> +char32_t t = U'\U0001F525';
> +#endif
> +wchar_t u = L'\u0065\u0301';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> +wchar_t v = L'é';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> --- gcc/testsuite/g++.dg/cpp23/wchar-multi2.C.jj	2022-08-25 18:51:53.744386945 +0200
> +++ gcc/testsuite/g++.dg/cpp23/wchar-multi2.C	2022-08-25 18:53:03.317489442 +0200
> @@ -0,0 +1,43 @@
> +// P2362R3 - Remove non-encodable wide character literals and multicharacter
> +// wide character literals.
> +// { dg-do compile }
> +// { dg-options "-fshort-wchar" }
> +
> +char a = 'a';
> +int b = 'ab';			// { dg-warning "multi-character character constant" }
> +int c = '\u05D9';		// { dg-warning "multi-character character constant" }
> +#if __SIZEOF_INT__ > 2
> +int d = '\U0001F525';		// { dg-warning "multi-character character constant" "" { target int32 } }
> +#endif
> +int e = 'abcd';			// { dg-warning "multi-character character constant" }
> +wchar_t f = L'f';
> +wchar_t g = L'gh';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> +wchar_t h = L'ijkl';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> +wchar_t i = L'\U0001F525';	// { dg-error "character constant too long for its type" "" { target { c++23 } } }
> +				// { dg-warning "character constant too long for its type" "" { target { c++20_down } } .-1 }
> +#ifdef __cpp_char8_t
> +typedef char8_t u8;
> +#else
> +typedef char u8;
> +#endif
> +#if __cpp_unicode_characters >= 201411
> +u8 j = u8'j';
> +u8 k = u8'kl';			// { dg-error "character constant too long for its type" "" { target c++17 } }
> +u8 l = u8'\U0001F525';		// { dg-error "character constant too long for its type" "" { target c++17 }  }
> +#endif
> +#if __cpp_unicode_characters >= 200704
> +char16_t m = u'm';
> +char16_t n = u'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
> +char16_t o = u'\u05D9';
> +char16_t p = u'\U0001F525';	// { dg-error "character constant too long for its type" "" { target c++11 } }
> +char32_t q = U'm';
> +char32_t r = U'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
> +char32_t s = U'\u05D9';
> +char32_t t = U'\U0001F525';
> +#endif
> +wchar_t u = L'\u0065\u0301';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> +wchar_t v = L'é';		// { dg-error "character constant too long for its type" "" { target c++23 } }
> +				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
> 
> 	Jakub
>
  

Patch

--- libcpp/charset.cc.jj	2022-08-25 11:54:38.849924475 +0200
+++ libcpp/charset.cc	2022-08-25 18:36:20.650415220 +0200
@@ -2170,7 +2170,11 @@  wide_str_to_charconst (cpp_reader *pfile
      character constant is guaranteed to overflow.  */
   if (str.len > nbwc * 2)
     cpp_error (pfile, (CPP_OPTION (pfile, cplusplus)
-		       && (type == CPP_CHAR16 || type == CPP_CHAR32))
+		       && (type == CPP_CHAR16
+			   || type == CPP_CHAR32
+			   /* In C++23 this is error even for L'ab'.  */
+			   || (type == CPP_WCHAR
+			       && CPP_OPTION (pfile, size_t_literals))))
 		      ? CPP_DL_ERROR : CPP_DL_WARNING,
 	       "character constant too long for its type");
 
--- gcc/testsuite/g++.dg/cpp23/wchar-multi1.C.jj	2022-08-25 18:08:01.973426155 +0200
+++ gcc/testsuite/g++.dg/cpp23/wchar-multi1.C	2022-08-25 18:51:30.476687112 +0200
@@ -0,0 +1,42 @@ 
+// P2362R3 - Remove non-encodable wide character literals and multicharacter
+// wide character literals.
+// { dg-do compile }
+
+char a = 'a';
+int b = 'ab';			// { dg-warning "multi-character character constant" }
+int c = '\u05D9';		// { dg-warning "multi-character character constant" }
+#if __SIZEOF_INT__ > 2
+int d = '\U0001F525';		// { dg-warning "multi-character character constant" "" { target int32 } }
+#endif
+int e = 'abcd';			// { dg-warning "multi-character character constant" }
+wchar_t f = L'f';
+wchar_t g = L'gh';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
+wchar_t h = L'ijkl';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
+wchar_t i = L'\U0001F525';	// { dg-error "character constant too long for its type" "" { target { c++23 && { ! 4byte_wchar_t } } } }
+				// { dg-warning "character constant too long for its type" "" { target { c++20_down && { ! 4byte_wchar_t } } } .-1 }
+#ifdef __cpp_char8_t
+typedef char8_t u8;
+#else
+typedef char u8;
+#endif
+#if __cpp_unicode_characters >= 201411 
+u8 j = u8'j';
+u8 k = u8'kl';			// { dg-error "character constant too long for its type" "" { target c++17 } }
+u8 l = u8'\U0001F525';		// { dg-error "character constant too long for its type" "" { target c++17 }  }
+#endif
+#if __cpp_unicode_characters >= 200704
+char16_t m = u'm';
+char16_t n = u'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
+char16_t o = u'\u05D9';
+char16_t p = u'\U0001F525';	// { dg-error "character constant too long for its type" "" { target c++11 } }
+char32_t q = U'm';
+char32_t r = U'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
+char32_t s = U'\u05D9';
+char32_t t = U'\U0001F525';
+#endif
+wchar_t u = L'\u0065\u0301';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
+wchar_t v = L'é';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
--- gcc/testsuite/g++.dg/cpp23/wchar-multi2.C.jj	2022-08-25 18:51:53.744386945 +0200
+++ gcc/testsuite/g++.dg/cpp23/wchar-multi2.C	2022-08-25 18:53:03.317489442 +0200
@@ -0,0 +1,43 @@ 
+// P2362R3 - Remove non-encodable wide character literals and multicharacter
+// wide character literals.
+// { dg-do compile }
+// { dg-options "-fshort-wchar" }
+
+char a = 'a';
+int b = 'ab';			// { dg-warning "multi-character character constant" }
+int c = '\u05D9';		// { dg-warning "multi-character character constant" }
+#if __SIZEOF_INT__ > 2
+int d = '\U0001F525';		// { dg-warning "multi-character character constant" "" { target int32 } }
+#endif
+int e = 'abcd';			// { dg-warning "multi-character character constant" }
+wchar_t f = L'f';
+wchar_t g = L'gh';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
+wchar_t h = L'ijkl';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
+wchar_t i = L'\U0001F525';	// { dg-error "character constant too long for its type" "" { target { c++23 } } }
+				// { dg-warning "character constant too long for its type" "" { target { c++20_down } } .-1 }
+#ifdef __cpp_char8_t
+typedef char8_t u8;
+#else
+typedef char u8;
+#endif
+#if __cpp_unicode_characters >= 201411 
+u8 j = u8'j';
+u8 k = u8'kl';			// { dg-error "character constant too long for its type" "" { target c++17 } }
+u8 l = u8'\U0001F525';		// { dg-error "character constant too long for its type" "" { target c++17 }  }
+#endif
+#if __cpp_unicode_characters >= 200704
+char16_t m = u'm';
+char16_t n = u'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
+char16_t o = u'\u05D9';
+char16_t p = u'\U0001F525';	// { dg-error "character constant too long for its type" "" { target c++11 } }
+char32_t q = U'm';
+char32_t r = U'no';		// { dg-error "character constant too long for its type" "" { target c++11 } }
+char32_t s = U'\u05D9';
+char32_t t = U'\U0001F525';
+#endif
+wchar_t u = L'\u0065\u0301';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }
+wchar_t v = L'é';		// { dg-error "character constant too long for its type" "" { target c++23 } }
+				// { dg-warning "character constant too long for its type" "" { target c++20_down } .-1 }