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Re: [wwwdocs] C++14 support for binary literals says Noinstead of Yes


On 04/27/2013 02:59 AM, Jakub Jelinek wrote:
On Sat, Apr 27, 2013 at 01:03:17AM -0400, Ed Smith-Rowland wrote:
In htdocs/projects/cxx1y.html it says no for support of binary
literals.  I think that's a Yes actually.

Here is a little patchlet.

Am I missing something?
So yes... ;-) I had tested on g++-4.1 and I guess pedantic let that go through back then. I swear -pedantic gave nothing... Oh well.

I like the patch.  It compiled and tested clean on x86_64-linux.

I'm working on a little proposal to add std::bin manipulator and related stuff in analogy to std::hex, etc. to the library. i think you should be able to write and extract binary literals.

Given
./xg++ -B ./ a.C -std=c++1y -pedantic-errors -S
a.C:1:9: error: binary constants are a GCC extension
  int i = 0b110101;
          ^

I'd say the fact that it is available as a GNU extension isn't sufficient to
mark this as supported.  I think you need something like (untested so far
except for make check-g++ RUNTESTFLAGS=*binary_const*):

2013-04-27  Jakub Jelinek<jakub@redhat.com>

	N3472 binary constants
	* include/cpplib.h (struct cpp_options): Fix a typo in user_literals
	field comment.  Add binary_constants field.
	* init.c (struct lang_flags): Add binary_constants field.
	(lang_defaults): Add bin_cst column to the table.
	(cpp_set_lang): Initialize CPP_OPTION (pfile, binary_constants).
	* expr.c (cpp_classify_number): Talk about C++11 instead of C++0x
	in diagnostics.  Accept binary constants if
	CPP_OPTION (pfile, binary_constants) even when pedantic.  Adjust
	pedwarn message.

	* g++.dg/cpp/limits.C: Adjust warning wording.
	* g++.dg/system-binary-constants-1.C: Likewise.
	* g++.dg/cpp1y/system-binary-constants-1.C: New test.

--- libcpp/include/cpplib.h.jj	2013-04-25 23:47:58.000000000 +0200
+++ libcpp/include/cpplib.h	2013-04-27 08:31:52.349122712 +0200
@@ -423,7 +423,7 @@ struct cpp_options
    /* True for traditional preprocessing.  */
    unsigned char traditional;
- /* Nonzero for C++ 2011 Standard user-defnied literals. */
+  /* Nonzero for C++ 2011 Standard user-defined literals.  */
    unsigned char user_literals;
/* Nonzero means warn when a string or character literal is followed by a
@@ -434,6 +434,9 @@ struct cpp_options
       literal number suffixes as user-defined literal number suffixes.  */
    unsigned char ext_numeric_literals;
+ /* Nonzero for C++ 2014 Standard binary constants. */
+  unsigned char binary_constants;
+
    /* Holds the name of the target (execution) character set.  */
    const char *narrow_charset;
--- libcpp/init.c.jj 2013-04-25 23:47:58.000000000 +0200
+++ libcpp/init.c	2013-04-27 08:34:54.103120530 +0200
@@ -83,24 +83,25 @@ struct lang_flags
    char uliterals;
    char rliterals;
    char user_literals;
+  char binary_constants;
  };
static const struct lang_flags lang_defaults[] =
-{ /*              c99 c++ xnum xid std  //   digr ulit rlit user_literals */
-  /* GNUC89   */  { 0,  0,  1,   0,  0,   1,   1,   0,   0,    0 },
-  /* GNUC99   */  { 1,  0,  1,   0,  0,   1,   1,   1,   1,    0 },
-  /* GNUC11   */  { 1,  0,  1,   0,  0,   1,   1,   1,   1,    0 },
-  /* STDC89   */  { 0,  0,  0,   0,  1,   0,   0,   0,   0,    0 },
-  /* STDC94   */  { 0,  0,  0,   0,  1,   0,   1,   0,   0,    0 },
-  /* STDC99   */  { 1,  0,  1,   0,  1,   1,   1,   0,   0,    0 },
-  /* STDC11   */  { 1,  0,  1,   0,  1,   1,   1,   1,   0,    0 },
-  /* GNUCXX   */  { 0,  1,  1,   0,  0,   1,   1,   0,   0,    0 },
-  /* CXX98    */  { 0,  1,  1,   0,  1,   1,   1,   0,   0,    0 },
-  /* GNUCXX11 */  { 1,  1,  1,   0,  0,   1,   1,   1,   1,    1 },
-  /* CXX11    */  { 1,  1,  1,   0,  1,   1,   1,   1,   1,    1 },
-  /* GNUCXX1Y */  { 1,  1,  1,   0,  0,   1,   1,   1,   1,    1 },
-  /* CXX1Y    */  { 1,  1,  1,   0,  1,   1,   1,   1,   1,    1 },
-  /* ASM      */  { 0,  0,  1,   0,  0,   1,   0,   0,   0,    0 }
+{ /*              c99 c++ xnum xid std  //   digr ulit rlit udlit bin_cst */
+  /* GNUC89   */  { 0,  0,  1,   0,  0,   1,   1,   0,   0,   0,    0 },
+  /* GNUC99   */  { 1,  0,  1,   0,  0,   1,   1,   1,   1,   0,    0 },
+  /* GNUC11   */  { 1,  0,  1,   0,  0,   1,   1,   1,   1,   0,    0 },
+  /* STDC89   */  { 0,  0,  0,   0,  1,   0,   0,   0,   0,   0,    0 },
+  /* STDC94   */  { 0,  0,  0,   0,  1,   0,   1,   0,   0,   0,    0 },
+  /* STDC99   */  { 1,  0,  1,   0,  1,   1,   1,   0,   0,   0,    0 },
+  /* STDC11   */  { 1,  0,  1,   0,  1,   1,   1,   1,   0,   0,    0 },
+  /* GNUCXX   */  { 0,  1,  1,   0,  0,   1,   1,   0,   0,   0,    0 },
+  /* CXX98    */  { 0,  1,  1,   0,  1,   1,   1,   0,   0,   0,    0 },
+  /* GNUCXX11 */  { 1,  1,  1,   0,  0,   1,   1,   1,   1,   1,    0 },
+  /* CXX11    */  { 1,  1,  1,   0,  1,   1,   1,   1,   1,   1,    0 },
+  /* GNUCXX1Y */  { 1,  1,  1,   0,  0,   1,   1,   1,   1,   1,    1 },
+  /* CXX1Y    */  { 1,  1,  1,   0,  1,   1,   1,   1,   1,   1,    1 },
+  /* ASM      */  { 0,  0,  1,   0,  0,   1,   0,   0,   0,   0,    0 }
    /* xid should be 1 for GNUC99, STDC99, GNUCXX, CXX98, GNUCXX11, CXX11,
       GNUCXX1Y, and CXX1Y when no longer experimental (when all uses of
       identifiers in the compiler have been audited for correct handling
@@ -126,6 +127,7 @@ cpp_set_lang (cpp_reader *pfile, enum c_
    CPP_OPTION (pfile, uliterals)			 = l->uliterals;
    CPP_OPTION (pfile, rliterals)			 = l->rliterals;
    CPP_OPTION (pfile, user_literals)		 = l->user_literals;
+  CPP_OPTION (pfile, binary_constants)		 = l->binary_constants;
  }
/* Initialize library global state. */
--- libcpp/expr.c.jj	2013-01-15 09:04:55.000000000 +0100
+++ libcpp/expr.c	2013-04-27 08:38:14.453026746 +0200
@@ -621,7 +621,7 @@ cpp_classify_number (cpp_reader *pfile,
  	  && CPP_OPTION (pfile, cpp_warn_long_long))
          {
            const char *message = CPP_OPTION (pfile, cplusplus)
-		                ? N_("use of C++0x long long integer constant")
+				? N_("use of C++11 long long integer constant")
  		                : N_("use of C99 long long integer constant");
if (CPP_OPTION (pfile, c99))
@@ -639,9 +639,14 @@ cpp_classify_number (cpp_reader *pfile,
    if ((result & CPP_N_IMAGINARY) && CPP_PEDANTIC (pfile))
      cpp_error_with_line (pfile, CPP_DL_PEDWARN, virtual_location, 0,
  			 "imaginary constants are a GCC extension");
-  if (radix == 2 && CPP_PEDANTIC (pfile))
+  if (radix == 2
+      && !CPP_OPTION (pfile, binary_constants)
+      && CPP_PEDANTIC (pfile))
      cpp_error_with_line (pfile, CPP_DL_PEDWARN, virtual_location, 0,
-			 "binary constants are a GCC extension");
+			 CPP_OPTION (pfile, cplusplus)
+			 ? "binary constants are a C++1y feature "
+			   "or GCC extension"
+			 : "binary constants are a GCC extension");
if (radix == 10)
      result |= CPP_N_DECIMAL;
--- gcc/testsuite/g++.dg/cpp/limits.C.jj	2012-06-06 20:35:54.000000000 +0200
+++ gcc/testsuite/g++.dg/cpp/limits.C	2013-04-27 08:45:20.036719569 +0200
@@ -4,13 +4,13 @@
  #include <limits>
// Compiling this with -pedantic was wrongly triggering this error:
-// libstdc++-v3/include/limits:1269:45: warning : use of C++0x long long integer constant [-Wlong-long]
+// libstdc++-v3/include/limits:1269:45: warning : use of C++11 long long integer constant [-Wlong-long]
  //       min() _GLIBCXX_USE_NOEXCEPT { return -__LONG_LONG_MAX__ - 1; }
  //                                             ^
-// libstdc++-v3/include/limits:1272:44: warning : use of C++0x long long integer constant [-Wlong-long]
+// libstdc++-v3/include/limits:1272:44: warning : use of C++11 long long integer constant [-Wlong-long]
  //       max() _GLIBCXX_USE_NOEXCEPT { return __LONG_LONG_MAX__; }
  //                                            ^
-// libstdc++-v3/include/limits:1342:44: warning : use of C++0x long long integer constant [-Wlong-long]
+// libstdc++-v3/include/limits:1342:44: warning : use of C++11 long long integer constant [-Wlong-long]
  //       max() _GLIBCXX_USE_NOEXCEPT { return __LONG_LONG_MAX__ * 2ULL + 1
  //                                            ^
--- gcc/testsuite/g++.dg/system-binary-constants-1.C.jj 2012-05-17 08:40:34.000000000 +0200
+++ gcc/testsuite/g++.dg/system-binary-constants-1.C	2013-04-27 08:47:50.600834156 +0200
@@ -14,5 +14,5 @@ foo (void)
  					    warning.  */
    return 23;
  #endif
-  return 0b1101; /* { dg-warning "binary constants are a GCC extension" } */
+  return 0b1101; /* { dg-warning "binary constants are a C..1y feature or GCC extension" } */
  }
--- gcc/testsuite/g++.dg/cpp1y/system-binary-constants-1.C.jj	2013-04-27 08:43:44.084238188 +0200
+++ gcc/testsuite/g++.dg/cpp1y/system-binary-constants-1.C	2013-04-27 08:52:35.687230081 +0200
@@ -0,0 +1,14 @@
+// Origin: Dodji Seketeli<dodji@redhat.com>
+// { dg-options "-std=c++1y -pedantic-errors" }
+// { dg-do compile }
+
+#include "../system-binary-constants-1.h"
+
+int
+foo (void)
+{
+#if BINARY_INT_CONSTANT_IN_SYSTEM_HEADER
+  return 23;
+#endif
+  return 0b1101; // { dg-bogus "binary constants are a C..1y feature or GCC extension" }
+}


	Jakub



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