c, libcpp: Partially implement C2Y N3353 paper [PR117028]

The following patch partially implements the N3353 paper.
In particular, it adds support for the delimited escape sequences
(\u{123}, \x{123}, \o{123}) which were added already for C++23,
all I had to do is split the delimited escape sequence guarding from
named universal character escape sequence guards
(\N{LATIN CAPITAL LETTER C WITH CARON}), which C++23 has but C2Y doesn't
and emit different diagnostics for C from C++ for the delimited escape
sequences.
And it adds support for the new style of octal literals, 0o137 or 0O1777.
I have so far added that just for C and not C++, because I have no idea
whether C++ will want to handle it similarly.

What the patch doesn't do is any kind of diagnostics for obsoletion of
\137 or 0137, as discussed in the PR, I think it is way too early for that.
Perhaps some non-default warning later on.

2024-10-17  Jakub Jelinek  <jakub@redhat.com>

	PR c/117028
libcpp/
	* include/cpplib.h (struct cpp_options): Add named_uc_escape_seqs,
	octal_constants and cpp_warn_c23_c2y_compat members.
	(enum cpp_warning_reason): Add CPP_W_C23_C2Y_COMPAT enumerator.
	* init.cc (struct lang_flags): Add named_uc_escape_seqs and
	octal_constants bit-fields.
	(lang_defaults): Add initializers for them into the table.
	(cpp_set_lang): Initialize named_uc_escape_seqs and octal_constants.
	(cpp_create_reader): Initialize cpp_warn_c23_c2y_compat to -1.
	* charset.cc (_cpp_valid_ucn): Test
	CPP_OPTION (pfile, named_uc_escape_seqs) rather than
	CPP_OPTION (pfile, delimited_escape_seqs) in \N{} related tests.
	Change wording of C cpp_pedwarning for \u{} and emit
	-Wc23-c2y-compat warning for it too if needed.  Formatting fixes.
	(convert_hex): Change wording of C cpp_pedwarning for \u{} and emit
	-Wc23-c2y-compat warning for it too if needed.
	(convert_oct): Likewise.
	* expr.cc (cpp_classify_number): Handle C2Y 0o or 0O prefixed
	octal constants.
	(cpp_interpret_integer): Likewise.
gcc/c-family/
	* c.opt (Wc23-c2y-compat): Add CPP and CppReason parameters.
	* c-opts.cc (set_std_c2y): Use CLK_STDC2Y or CLK_GNUC2Y rather
	than CLK_STDC23 and CLK_GNUC23.  Formatting fix.
	* c-lex.cc (interpret_integer): Handle C2Y 0o or 0O prefixed
	and wb/WB/uwb/UWB suffixed octal constants.
gcc/testsuite/
	* gcc.dg/bitint-112.c: New test.
	* gcc.dg/c23-digit-separators-1.c: Add _Static_assert for
	valid binary constant with digit separator.
	* gcc.dg/c23-octal-constants-1.c: New test.
	* gcc.dg/c23-octal-constants-2.c: New test.
	* gcc.dg/c2y-digit-separators-1.c: New test.
	* gcc.dg/c2y-digit-separators-2.c: New test.
	* gcc.dg/c2y-octal-constants-1.c: New test.
	* gcc.dg/c2y-octal-constants-2.c: New test.
	* gcc.dg/c2y-octal-constants-3.c: New test.
	* gcc.dg/cpp/c23-delimited-escape-seq-1.c: New test.
	* gcc.dg/cpp/c23-delimited-escape-seq-2.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-1.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-2.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-3.c: New test.
	* gcc.dg/cpp/c2y-delimited-escape-seq-4.c: New test.
	* gcc.dg/octal-constants-1.c: New test.
	* gcc.dg/octal-constants-2.c: New test.
	* gcc.dg/octal-constants-3.c: New test.
	* gcc.dg/octal-constants-4.c: New test.
	* gcc.dg/system-octal-constants-1.c: New test.
	* gcc.dg/system-octal-constants-1.h: New file.

4 files changed, 142 insertions, 53 deletions

diff --git a/libcpp/charset.cc b/libcpp/charset.cc
index bcfc10c..cc38769 100644
--- a/libcpp/charset.cc
+++ b/libcpp/charset.cc
@@ -1579,7 +1579,7 @@ _cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
     {
       length = 4;
       if (identifier_pos
-	  && !CPP_OPTION (pfile, delimited_escape_seqs)
+	  && !CPP_OPTION (pfile, named_uc_escape_seqs)
 	  && CPP_OPTION (pfile, std))
 	{
 	  *cp = 0;
@@ -1631,7 +1631,7 @@ _cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
 		cpp_error (pfile, CPP_DL_ERROR,
 			   "empty named universal character escape sequence");
 	      else if ((!identifier_pos || strict)
-		       && !CPP_OPTION (pfile, delimited_escape_seqs)
+		       && !CPP_OPTION (pfile, named_uc_escape_seqs)
 		       && CPP_OPTION (pfile, cpp_pedantic))
 		cpp_pedwarning (pfile,
 				CPP_OPTION (pfile, cplusplus)
@@ -1653,7 +1653,7 @@ _cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
 		    {
 		      bool ret = true;
 		      if (identifier_pos
-			  && (!CPP_OPTION (pfile, delimited_escape_seqs)
+			  && (!CPP_OPTION (pfile, named_uc_escape_seqs)
 			      || !strict))
 			ret = cpp_warning (pfile, CPP_W_UNICODE,
 					   "%<\\N{%.*s}%> is not a valid "
@@ -1676,7 +1676,7 @@ _cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
 		      else
 			result = 0xC0;
 		      if (identifier_pos
-			  && (!CPP_OPTION (pfile, delimited_escape_seqs)
+			  && (!CPP_OPTION (pfile, named_uc_escape_seqs)
 			      || !strict))
 			{
 			  *cp = 0;
@@ -1746,6 +1746,7 @@ _cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
 
   if (delimited && str < limit && *str == '}')
     {
+      bool warned = false;
       if (length == 32 && identifier_pos)
 	{
 	  cpp_warning (pfile, CPP_W_UNICODE,
@@ -1755,13 +1756,28 @@ _cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
 	  return false;
 	}
       else if (length == 32)
-	cpp_error (pfile, CPP_DL_ERROR,
-		   "empty delimited escape sequence");
+	{
+	  cpp_error (pfile, CPP_DL_ERROR, "empty delimited escape sequence");
+	  warned = true;
+	}
       else if (!CPP_OPTION (pfile, delimited_escape_seqs)
 	       && CPP_OPTION (pfile, cpp_pedantic))
-	cpp_pedwarning (pfile, (CPP_OPTION (pfile, cplusplus)
-				? CPP_W_CXX23_EXTENSIONS : CPP_W_PEDANTIC),
-			"delimited escape sequences are only valid in C++23");
+	{
+	  if (CPP_OPTION (pfile, cplusplus))
+	    warned
+	      = cpp_pedwarning (pfile, CPP_W_CXX23_EXTENSIONS,
+				"delimited escape sequences are only valid "
+				"in C++23");
+	  else
+	    warned
+	      = cpp_pedwarning (pfile, CPP_W_PEDANTIC,
+				"delimited escape sequences are only valid "
+				"in C2Y");
+	}
+      if (!warned && CPP_OPTION (pfile, cpp_warn_c23_c2y_compat) > 0)
+	cpp_warning (pfile, CPP_W_C11_C23_COMPAT,
+		     "delimited escape sequences are only valid in C2Y");
+
       str++;
       length = 0;
       delimited = false;
@@ -2125,6 +2141,7 @@ convert_hex (cpp_reader *pfile, const uchar *from, const uchar *limit,
 
   if (delimited && from < limit && *from == '}')
     {
+      bool warned = false;
       from++;
       if (!digits_found)
 	{
@@ -2134,9 +2151,21 @@ convert_hex (cpp_reader *pfile, const uchar *from, const uchar *limit,
 	}
       else if (!CPP_OPTION (pfile, delimited_escape_seqs)
 	       && CPP_OPTION (pfile, cpp_pedantic))
-	cpp_pedwarning (pfile, (CPP_OPTION (pfile, cplusplus)
-				? CPP_W_CXX23_EXTENSIONS : CPP_W_PEDANTIC),
-			"delimited escape sequences are only valid in C++23");
+	{
+	  if (CPP_OPTION (pfile, cplusplus))
+	    warned
+	      = cpp_pedwarning (pfile, CPP_W_CXX23_EXTENSIONS,
+				"delimited escape sequences are only valid "
+				"in C++23");
+	  else
+	    warned
+	      = cpp_pedwarning (pfile, CPP_W_PEDANTIC,
+				"delimited escape sequences are only valid "
+				"in C2Y");
+	}
+      if (!warned && CPP_OPTION (pfile, cpp_warn_c23_c2y_compat) > 0)
+	cpp_warning (pfile, CPP_W_C11_C23_COMPAT,
+		     "delimited escape sequences are only valid in C2Y");
       delimited = false;
       extend_char_range (&char_range, loc_reader);
     }
@@ -2229,6 +2258,7 @@ convert_oct (cpp_reader *pfile, const uchar *from, const uchar *limit,
     {
       if (from < limit && *from == '}')
 	{
+	  bool warned = false;
 	  from++;
 	  if (count == 1)
 	    {
@@ -2238,10 +2268,21 @@ convert_oct (cpp_reader *pfile, const uchar *from, const uchar *limit,
 	    }
 	  else if (!CPP_OPTION (pfile, delimited_escape_seqs)
 		   && CPP_OPTION (pfile, cpp_pedantic))
-	    cpp_pedwarning (pfile, (CPP_OPTION (pfile, cplusplus)
-				    ? CPP_W_CXX23_EXTENSIONS : CPP_W_PEDANTIC),
-			    "delimited escape sequences are only valid "
-			    "in C++23");
+	    {
+	      if (CPP_OPTION (pfile, cplusplus))
+		warned
+		  = cpp_pedwarning (pfile, CPP_W_CXX23_EXTENSIONS,
+				    "delimited escape sequences are only "
+				    "valid in C++23");
+	      else
+		warned
+		  = cpp_pedwarning (pfile, CPP_W_PEDANTIC,
+				    "delimited escape sequences are only "
+				    "valid in C2Y");
+	    }
+	  if (!warned && CPP_OPTION (pfile, cpp_warn_c23_c2y_compat) > 0)
+	    cpp_warning (pfile, CPP_W_C11_C23_COMPAT,
+			 "delimited escape sequences are only valid in C2Y");
 	  extend_char_range (&char_range, loc_reader);
 	}
       else
diff --git a/libcpp/expr.cc b/libcpp/expr.cc
index 67d021f..2a57dc79d 100644
--- a/libcpp/expr.cc
+++ b/libcpp/expr.cc
@@ -556,6 +556,7 @@ cpp_classify_number (cpp_reader *pfile, const cpp_token *token,
   enum {NOT_FLOAT = 0, AFTER_POINT, AFTER_EXPON} float_flag;
   bool seen_digit;
   bool seen_digit_sep;
+  bool zero_o_prefix;
 
   if (ud_suffix)
     *ud_suffix = NULL;
@@ -571,6 +572,7 @@ cpp_classify_number (cpp_reader *pfile, const cpp_token *token,
   radix = 10;
   seen_digit = false;
   seen_digit_sep = false;
+  zero_o_prefix = false;
 
   /* First, interpret the radix.  */
   if (*str == '0')
@@ -601,6 +603,17 @@ cpp_classify_number (cpp_reader *pfile, const cpp_token *token,
 	    SYNTAX_ERROR_AT (virtual_location,
 			     "digit separator after base indicator");
 	}
+      else if ((*str == 'o' || *str == 'O') && !CPP_OPTION (pfile, cplusplus))
+	{
+	  if (ISDIGIT (str[1]))
+	    {
+	      zero_o_prefix = true;
+	      str++;
+	    }
+	  else if (DIGIT_SEP (str[1]))
+	    SYNTAX_ERROR_AT (virtual_location,
+			     "digit separator after base indicator");
+	}
     }
 
   /* Now scan for a well-formed integer or float.  */
@@ -694,6 +707,12 @@ cpp_classify_number (cpp_reader *pfile, const cpp_token *token,
 			       "invalid prefix %<0b%> for floating constant");
 	  return CPP_N_INVALID;
 	}
+      if (zero_o_prefix)
+	{
+	  cpp_error_with_line (pfile, CPP_DL_ERROR, virtual_location, 0,
+			       "invalid prefix %<0o%> for floating constant");
+	  return CPP_N_INVALID;
+	}
 
       if (radix == 16 && !seen_digit)
 	SYNTAX_ERROR_AT (virtual_location,
@@ -897,8 +916,7 @@ cpp_classify_number (cpp_reader *pfile, const cpp_token *token,
   if (radix == 2)
     {
       bool warned = false;
-      if (!CPP_OPTION (pfile, binary_constants)
-	  && CPP_PEDANTIC (pfile))
+      if (!CPP_OPTION (pfile, binary_constants) && CPP_PEDANTIC (pfile))
 	{
 	  if (CPP_OPTION (pfile, cplusplus))
 	    warned
@@ -916,6 +934,19 @@ cpp_classify_number (cpp_reader *pfile, const cpp_token *token,
 			       virtual_location, 0,
 			       "binary constants are a C23 feature");
     }
+  if (zero_o_prefix)
+    {
+      bool warned = false;
+      if (!CPP_OPTION (pfile, octal_constants) && CPP_PEDANTIC (pfile))
+	warned
+	  = cpp_pedwarning_with_line (pfile, CPP_W_PEDANTIC, virtual_location,
+				      0, "%<0o%> prefixed constants are a C2Y "
+					 "feature or GCC extension");
+      if (!warned && CPP_OPTION (pfile, cpp_warn_c23_c2y_compat) > 0)
+	cpp_warning_with_line (pfile, CPP_W_C23_C2Y_COMPAT,
+			       virtual_location, 0,
+			       "%<0o%> prefixed constants are a C2Y feature");
+    }
 
   if (radix == 10)
     result |= CPP_N_DECIMAL;
@@ -967,6 +998,8 @@ cpp_interpret_integer (cpp_reader *pfile, const cpp_token *token,
 	{
 	  base = 8;
 	  p++;
+	  if (*p == 'o' || *p == 'O')
+	    p++;
 	}
       else if ((type & CPP_N_RADIX) == CPP_N_HEX)
 	{
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 0d11d07..5441229 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -548,6 +548,12 @@ struct cpp_options
   /* Nonzero for C++23 delimited escape sequences.  */
   unsigned char delimited_escape_seqs;
 
+  /* Nonzero for C++23 named universal character escape sequences.  */
+  unsigned char named_uc_escape_seqs;
+
+  /* Nonzero for C2Y 0o prefixed octal integer constants.  */
+  unsigned char octal_constants;
+
   /* Nonzero for 'true' and 'false' in #if expressions.  */
   unsigned char true_false;
 
@@ -579,6 +585,9 @@ struct cpp_options
   /* True if warn about differences between C11 and C23.  */
   signed char cpp_warn_c11_c23_compat;
 
+  /* True if warn about differences between C23 and C2Y.  */
+  signed char cpp_warn_c23_c2y_compat;
+
   /* True if warn about differences between C++98 and C++11.  */
   bool cpp_warn_cxx11_compat;
 
@@ -716,6 +725,7 @@ enum cpp_warning_reason {
   CPP_W_PEDANTIC,
   CPP_W_C90_C99_COMPAT,
   CPP_W_C11_C23_COMPAT,
+  CPP_W_C23_C2Y_COMPAT,
   CPP_W_CXX11_COMPAT,
   CPP_W_CXX20_COMPAT,
   CPP_W_CXX14_EXTENSIONS,
diff --git a/libcpp/init.cc b/libcpp/init.cc
index 1cc62a4..4789274 100644
--- a/libcpp/init.cc
+++ b/libcpp/init.cc
@@ -108,46 +108,48 @@ struct lang_flags
   unsigned int elifdef : 1;
   unsigned int warning_directive : 1;
   unsigned int delimited_escape_seqs : 1;
+  unsigned int named_uc_escape_seqs : 1;
+  unsigned int octal_constants : 1;
   unsigned int true_false : 1;
   unsigned int embed : 1;
 };
 
 static const struct lang_flags lang_defaults[] = {
-  /*					       u         e w
-					 b d   8         l a   t
-			     x         u i i   c v s   s i r d r e
-		       x     i   d u r d n g t h a c   z f n e u m
-		   c c n x c d s i l l l c s r l o o d l d d l f b
-		   9 + u i 1 i t g i i i s e i i p p f i e i i a e
-		   9 + m d 1 d d r t t t t p g t t e p t f r m l d  */
-  /* GNUC89   */ { 0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0 },
-  /* GNUC99   */ { 1,0,1,1,0,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0 },
-  /* GNUC11   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0 },
-  /* GNUC17   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0 },
-  /* GNUC23   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,0,1,1 },
-  /* GNUC2Y   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,0,1,1 },
-  /* STDC89   */ { 0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC94   */ { 0,0,0,0,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC99   */ { 1,0,1,1,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC11   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC17   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0 },
-  /* STDC23   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,0,1,1 },
-  /* STDC2Y   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,0,1,1 },
-  /* GNUCXX   */ { 0,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,1,0 },
-  /* CXX98    */ { 0,1,0,1,0,1,1,1,0,0,0,0,0,1,0,0,1,0,0,0,0,0,1,0 },
-  /* GNUCXX11 */ { 1,1,1,1,1,1,0,1,1,1,1,0,0,0,0,1,1,0,0,0,0,0,1,0 },
-  /* CXX11    */ { 1,1,0,1,1,1,1,1,1,1,1,0,0,1,0,0,1,0,0,0,0,0,1,0 },
-  /* GNUCXX14 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,0,1,1,0,0,0,0,0,1,0 },
-  /* CXX14    */ { 1,1,0,1,1,1,1,1,1,1,1,1,1,1,0,0,1,0,0,0,0,0,1,0 },
-  /* GNUCXX17 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,1,0 },
-  /* CXX17    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1,0,0,0,0,0,1,0 },
-  /* GNUCXX20 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,1,0 },
-  /* CXX20    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,1,0 },
-  /* GNUCXX23 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0 },
-  /* CXX23    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0 },
-  /* GNUCXX26 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0 },
-  /* CXX26    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0 },
-  /* ASM      */ { 0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }
+  /*					       u         e w   n
+					 b d   8         l a   a   t
+			     x         u i i   c v s   s i r d m o r e
+		       x     i   d u r d n g t h a c   z f n e e c u m
+		   c c n x c d s i l l l c s r l o o d l d d l d t f b
+		   9 + u i 1 i t g i i i s e i i p p f i e i i u a a e
+		   9 + m d 1 d d r t t t t p g t t e p t f r m c l l d  */
+  /* GNUC89   */ { 0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
+  /* GNUC99   */ { 1,0,1,1,0,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
+  /* GNUC11   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
+  /* GNUC17   */ { 1,0,1,1,1,0,0,1,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0 },
+  /* GNUC23   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,0,0,0,1,1 },
+  /* GNUC2Y   */ { 1,0,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,1 },
+  /* STDC89   */ { 0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC94   */ { 0,0,0,0,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC99   */ { 1,0,1,1,0,0,1,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC11   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC17   */ { 1,0,1,1,1,0,1,1,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0 },
+  /* STDC23   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,0,0,0,1,1 },
+  /* STDC2Y   */ { 1,0,1,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,0,1,1,1,0,1,1,1 },
+  /* GNUCXX   */ { 0,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,1,0 },
+  /* CXX98    */ { 0,1,0,1,0,1,1,1,0,0,0,0,0,1,0,0,1,0,0,0,0,0,0,0,1,0 },
+  /* GNUCXX11 */ { 1,1,1,1,1,1,0,1,1,1,1,0,0,0,0,1,1,0,0,0,0,0,0,0,1,0 },
+  /* CXX11    */ { 1,1,0,1,1,1,1,1,1,1,1,0,0,1,0,0,1,0,0,0,0,0,0,0,1,0 },
+  /* GNUCXX14 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,0,1,1,0,0,0,0,0,0,0,1,0 },
+  /* CXX14    */ { 1,1,0,1,1,1,1,1,1,1,1,1,1,1,0,0,1,0,0,0,0,0,0,0,1,0 },
+  /* GNUCXX17 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0 },
+  /* CXX17    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1,0,0,0,0,0,0,0,1,0 },
+  /* GNUCXX20 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0 },
+  /* CXX20    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,0,0,0,0,0,0,1,0 },
+  /* GNUCXX23 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
+  /* CXX23    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
+  /* GNUCXX26 */ { 1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
+  /* CXX26    */ { 1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0 },
+  /* ASM      */ { 0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }
 };
 
 /* Sets internal flags correctly for a given language.  */
@@ -180,6 +182,8 @@ cpp_set_lang (cpp_reader *pfile, enum c_lang lang)
   CPP_OPTION (pfile, elifdef)			 = l->elifdef;
   CPP_OPTION (pfile, warning_directive)		 = l->warning_directive;
   CPP_OPTION (pfile, delimited_escape_seqs)	 = l->delimited_escape_seqs;
+  CPP_OPTION (pfile, named_uc_escape_seqs)	 = l->named_uc_escape_seqs;
+  CPP_OPTION (pfile, octal_constants)		 = l->octal_constants;
   CPP_OPTION (pfile, true_false)		 = l->true_false;
   CPP_OPTION (pfile, embed)			 = l->embed;
 }
@@ -230,6 +234,7 @@ cpp_create_reader (enum c_lang lang, cpp_hash_table *table,
   CPP_OPTION (pfile, warn_endif_labels) = 1;
   CPP_OPTION (pfile, cpp_warn_c90_c99_compat) = -1;
   CPP_OPTION (pfile, cpp_warn_c11_c23_compat) = -1;
+  CPP_OPTION (pfile, cpp_warn_c23_c2y_compat) = -1;
   CPP_OPTION (pfile, cpp_warn_cxx11_compat) = 0;
   CPP_OPTION (pfile, cpp_warn_cxx20_compat) = 0;
   CPP_OPTION (pfile, cpp_warn_deprecated) = 1;