4.7 version of c99status.html

["Joseph S. Myers"]

I've created the 4.7 version of c99status.html and made the 4.7 branch 
manual refer to it instead of the mainline version of the page.  Doc patch 
tested with "make info html pdf".

Index: c99status.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/c99status.html,v
retrieving revision 1.57
diff -u -r1.57 c99status.html
--- c99status.html	18 Mar 2011 17:47:35 -0000	1.57
+++ c99status.html	13 Mar 2012 23:11:10 -0000
@@ -21,6 +21,7 @@
 
 
This page describes the C99 support in mainline GCC, not in any
 particular release.  Information is also available on C99 support in GCC 4.7, C99 support in GCC 4.6, C99 support in GCC 4.5, C99 support in GCC 4.4, 
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Status of C99 features in GCC 4.7

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This table is based on the list in the foreword to http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf";>N1256
+(ISO/IEC 9899:1999 (E), consolidated with ISO/IEC 9899:1999/Cor.1:2001
+(E), ISO/IEC 9899:1999/Cor.2:2004 (E) and ISO/IEC 9899:1999/Cor.3:2007
+(E)).
+
+
Where "Library Issue" is listed in conjunction with some other
+status, this means that some compiler support is needed for the
+library support, or desirable in conjunction with it.  Note that the
+headers required of conforming freestanding implementations (clause 4
+paragraph 6) do not count as library issues.
+
+
This page describes the C99 support in GCC 4.7.  Information on C99 support in mainline GCC is also
+available.
+
+
See below the table for further notes on some issues.
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Feature
Library Issue
Done
Broken
Missing
restricted character set support via digraphs and
+    
<iso646.h> (originally specified in AMD1)
Done
wide character library support in
+    <wchar.h>
and <wctype.h>
+    (originally specified in AMD1)
Library Issue
Missing
more precise aliasing rules via effective type
Done
restricted pointers
Done
variable-length arrays
Done
flexible array members
Done
static and type qualifiers
in parameter array declarators
Done
complex (and imaginary) support in <complex.h>
Done
type-generic math macros in <tgmath.h>
Library Issue
Done
the long long int type and library functions
Done
increased minimum translation limits
Done
additional floating-point characteristics
in <float.h>
Done
remove implicit int
Done
reliable integer division
Done
universal character names (\u and \U)
Done
extended identifiers
Missing
hexadecimal floating-point constants and
+    %a
 and %A
+    printf/scanf conversion specifiers
Library Issue
Done
compound literals
Done
designated initializers
Done
// comments
Done
library functions in <inttypes.h>
Library Issue
extended integer types in <stdint.h>
Missing
remove implicit function declaration
Done
preprocessor arithmetic
done in intmax_t/uintmax_t
Done
mixed declarations and code
Done
new block scopes for selection
and iteration statements
Done
integer constant type rules
Done
integer promotion rules
Done
macros with a variable number of arguments
Done
the vscanf family of functions
+    in
<stdio.h> and <wchar.h>
Library Issue
Done
additional math library functions in <math.h>
Library Issue
treatment of error conditions by math library functions (math_errhandling)
Library Issue
Missing
floating-point environment access
in <fenv.h>
Library Issue
IEC 60559 (also known as
IEC 559 or IEEE arithmetic) support
Broken
trailing comma allowed in enum declaration
Done
%lf conversion specifier
allowed in printf
Library Issue
Done
inline functions
Done
the snprintf family of functions in <stdio.h>
Library Issue
Done
boolean type in <stdbool.h>
Done
idempotent type qualifiers
Done
empty macro arguments
Done
new struct type compatibility
rules (tag compatibility)
Done
additional predefined macro names
Missing
_Pragma preprocessing operator
Done
standard pragmas
Missing
__func__ predefined identifier
Done
va_copy macro
Done
additional strftime conversion specifiers
Library Issue
Done
deprecate ungetc at the
beginning of a binary file
Library Issue
remove deprecation of
aliased array parameters
Done
conversion of array to pointer not limited to lvalues
Done
relaxed constraints on aggregate
and union initialization
Done
relaxed restrictions on portable header names
Done
return without expression not permitted
+    in
function that returns a value (and vice versa)
Done
Feature
Library Issue
Done
Broken
Missing
+
+
Further notes
+
+

+
+
cpp has limited support for multibyte character sets.
+
+
IEC 60559 is IEEE 754 floating point.  This works if and only if
+the hardware is perfectly compliant, but GCC does not define
+__STDC_IEC_559__ or implement the associated standard
+pragmas; nor do some options such as -frounding-math to
+enable the pragmas globally work in all cases (for example, required
+exceptions may not be generated) and contracting expressions (e.g.,
+using fused multiply-add) is not restricted to source-language
+expressions as required by C99.
+
+
Compiler support is needed for thorough support of math_errhandling; see
+messages http://sources.redhat.com/ml/libc-hacker/2000-06/msg00008.html";>1,
+http://sources.redhat.com/ml/libc-hacker/2000-06/msg00014.html";>2,
+http://sources.redhat.com/ml/libc-hacker/2000-06/msg00015.html";>3
+on this subject to libc-hacker.  The compiler needs to mark its output
+from compilations using -fno-trapping-math
+or -fno-math-errno, possibly using
+the .gnu_attribute mechanism, to indicate that built-in
+function optimizations may have been applied that mean that not all
+calls report error status in a particular way; the static linker
+needs to put this information in executables and shared libraries and
+the C library needs to use it to set math_errhandling at
+startup to a conservatively correct value based on the information
+from the compiler.  There is currently some limited GNU C Library
+support that only conforms as long as the above options are not used
+anywhere in the program.
+
+
GCC doesn't have wprintf, wscanf and
+wcsftime format checking support.
+
+
GCC does not support the Annex G imaginary types and complex
+multiplication and division have excess overflows at runtime (although
+not beyond those permitted by C99).
+
+
<stdint.h> is provided by GCC, or fixed where
+the system headers provide a nonconforming version, on some but not
+yet all systems.  On systems where types in this header have been
+defined as char, GCC retains this definition although it
+is not permitted by C99.
+
+
Some of the C99 predefined macros represent properties of the
+compiler and library together and so defining them for the whole
+translation unit requires cooperation with the library;
+a http://sourceware.org/ml/libc-alpha/2009-04/msg00005.html";>GNU
+C Library patch for this is pending review.
+
+
const-qualified compound literals could share storage
+with each other and with string literals, but currently don't.
+
+
The information provided by static in parameter array
+declarators is not used for optimization.  It might make sense to use
+it in future in conjunction with work
+on prefetching.
+
+
The list above differs from that in N1256 as follows:
+"LIA compatibility annex" is removed, since it refers to C99's
+conformance to another standard rather than something for C
+implementations to do.  The <stdint.h> and
+<inttypes.h> entries have been separated, but are a
+single entry in C99.
+
+
+
+
+
Index: doc/standards.texi
===================================================================
--- doc/standards.texi	(revision 185363)
+++ doc/standards.texi	(working copy)
@@ -88,7 +88,7 @@
 A new edition of the ISO C standard was published in 1999 as ISO/IEC
 9899:1999, and is commonly known as @dfn{C99}.  GCC has incomplete
 support for this standard version; see
-@uref{http://gcc.gnu.org/c99status.html} for details.  To select this
+@uref{http://gcc.gnu.org/gcc-4.7/c99status.html} for details.  To select this
 standard, use @option{-std=c99} or @option{-std=iso9899:1999}.  (While in
 development, drafts of this standard version were referred to as
 @dfn{C9X}.)
Index: doc/invoke.texi
===================================================================
--- doc/invoke.texi	(revision 185363)
+++ doc/invoke.texi	(working copy)
@@ -1570,7 +1570,7 @@
 @itemx iso9899:1999
 @itemx iso9899:199x
 ISO C99.  Note that this standard is not yet fully supported; see
-@w{@uref{http://gcc.gnu.org/c99status.html}} for more information.  The
+@w{@uref{http://gcc.gnu.org/gcc-4.7/c99status.html}} for more information.  The
 names @samp{c9x} and @samp{iso9899:199x} are deprecated.
 
 @item c11
Index: ChangeLog
===================================================================
--- ChangeLog	(revision 185363)
+++ ChangeLog	(working copy)
@@ -1,3 +1,8 @@
+2012-03-13  Joseph Myers  
+
+	* doc/invoke.texi (-std=c99), doc/standards.texi (C language):
+	Refer to GCC 4.7 version of c99status.html.
+
 2012-03-12  Michael Meissner  
 
 	Backport from mainline

-- 
Joseph S. Myers
joseph@codesourcery.com