c-lex.c (parse_float, yylex): For -Wtraditional, issue a warning about…

c-lex.c (parse_float, yylex): For -Wtraditional, issue a warning about non-traditional numeric constant suffixes.

	* c-lex.c (parse_float, yylex): For -Wtraditional, issue a
	warning about non-traditional numeric constant suffixes.

	* cppexp.c (parse_number): Likewise.

	* invoke.texi: (-Wtraditional): Document new behavior.

From-SVN: r35607

gcc/ChangeLog

+2000-08-10  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
+
+	* c-lex.c (parse_float, yylex): For -Wtraditional, issue a
+	warning about non-traditional numeric constant suffixes.
+
+	* cppexp.c (parse_number): Likewise.
+
+	* invoke.texi: (-Wtraditional): Document new behavior.
+
 Thu Aug 10 00:11:04 2000  Ovidiu Predescu  <ovidiu@cup.hp.com>
 
 	* gthr-posix.h: Include auto-host.h. Conditionally include

gcc/c-lex.c

@@ -1109,12 +1109,16 @@ parse_float (data)
 	case 'f': case 'F':
 	  if (fflag)
 	    error ("more than one `f' in numeric constant");
+	  else if (warn_traditional && !in_system_header)
+	    warning ("traditional C rejects the `%c' suffix", args->c);
 	  fflag = 1;
 	  break;
 
 	case 'l': case 'L':
 	  if (lflag)
 	    error ("more than one `l' in numeric constant");
+	  else if (warn_traditional && !in_system_header)
+	    warning ("traditional C rejects the `%c' suffix", args->c);
 	  lflag = 1;
 	  break;
 
@@ -1773,6 +1777,8 @@ yylex ()
 		  {
 		    if (spec_unsigned)
 		      error ("two `u's in integer constant");
+ 		    else if (warn_traditional && !in_system_header)
+ 		      warning ("traditional C rejects the `%c' suffix", c);
 		    spec_unsigned = 1;
 		    if (spec_long)
 		      suffix_lu = 1;

gcc/cppexp.c

@@ -218,6 +218,8 @@ parse_number (pfile, tok)
 	goto invalid_suffix;
       op.unsignedp = sufftab[i].u;
 
+      if (CPP_WTRADITIONAL (pfile) && sufftab[i].u)
+	cpp_warning (pfile, "traditional C rejects the `U' suffix");
       if (CPP_OPTION (pfile, c89) && sufftab[i].l == 2)
 	SYNTAX_ERROR ("too many 'l' suffixes in integer constant");
     }

gcc/invoke.texi

@@ -1838,6 +1838,15 @@ omitted.  This is done under the assumption that the zero initializer in
 user code appears conditioned on e.g. @code{__STDC__} to avoid missing
 initializer warnings and relies on default initialization to zero in the
 traditional C case.
+
+@item
+The `U' integer constant suffix, or the `F' or `L' floating point
+constant suffixes.  (Traditonal C does support the `L' suffix on integer
+constants.)  Note, these suffixes appear in macros defined in the system
+headers of most modern systems, e.g. the _MIN/_MAX macros in limits.h.
+Use of these macros can lead to spurious warnings as they do not
+necessarily reflect whether the code in question is any less portable to
+traditional C given that suitable backup definitions are provided.
 @end itemize
 
 @item -Wundef