Re: C1X _Noreturn
Joseph S. Myers jos...@codesourcery.com writes: I didn't touch the USER_H definition in mips/t-sdemtk (so that target will not install this new header). The comment Remove stdarg.h and stddef.h from USER_H. suggests that maybe it should be added to that definition, but stdfix.h is also missing from that definition. As far as I know MIPS is no longer using the old SDE library and it is considered superseded by newlib, so perhaps that configuration (mips*-sde-elf* without newlib) should actually be deprecated/removed (and mipssde threads along with it). BTW, do you know whether the same applies to -mno-float, which at the moment is specific to sdemtk? That option was never really implemented, and just relied on the user being very, very careful. It would be nice to deprecate it at the same time. If so, I'll do a patch this weekend to deprecate all three (the thread model, the option, and the configuration). Richard
Re: C1X _Noreturn
On Wed, 24 Aug 2011, Richard Sandiford wrote: Joseph S. Myers jos...@codesourcery.com writes: I didn't touch the USER_H definition in mips/t-sdemtk (so that target will not install this new header). The comment Remove stdarg.h and stddef.h from USER_H. suggests that maybe it should be added to that definition, but stdfix.h is also missing from that definition. As far as I know MIPS is no longer using the old SDE library and it is considered superseded by newlib, so perhaps that configuration (mips*-sde-elf* without newlib) should actually be deprecated/removed (and mipssde threads along with it). BTW, do you know whether the same applies to -mno-float, which at the moment is specific to sdemtk? That option was never really implemented, and just relied on the user being very, very careful. It would be nice to deprecate it at the same time. I don't know - Catherine, do you know if MIPS has ceased to use -mno-float along with replacing the SDE library with newlib? -- Joseph S. Myers jos...@codesourcery.com
Re: C1X _Noreturn
On 08/18/2011 11:37 PM, Joseph S. Myers wrote: C1X provides a standard way of declaring non-returning functions, with the _Noreturn keyword and a header stdnoreturn.h defining a macro noreturn to expand to _Noreturn. This patch implements this syntax and header. Bootstrapped with no regressions on x86_64-unknown-linux-gnu. Applied to mainline. I didn't touch the USER_H definition in mips/t-sdemtk (so that target will not install this new header). The comment Remove stdarg.h and stddef.h from USER_H. suggests that maybe it should be added to that definition, but stdfix.h is also missing from that definition. As far as I know MIPS is no longer using the old SDE library and it is considered superseded by newlib, so perhaps that configuration (mips*-sde-elf* without newlib) should actually be deprecated/removed (and mipssde threads along with it). The new keyword is C-only (C++0x has a different way of declaring non-returning functions) and I did not try to make the header do anything useful if included in C++ code. 2011-08-18 Joseph Myersjos...@codesourcery.com * c-decl.c (shadow_tag_warned): Check for _Noreturn. (quals_from_declspecs): Assert _Noreturn not present. (grokdeclarator): Handle _Noreturn. (build_null_declspecs): Initialize noreturn_p. (declspecs_add_scspec): Handle RID_NORETURN. * c-parser.c (c_token_starts_declspecs, c_parser_declspecs) (c_parser_attributes): Handle RID_NORETURN. * c-tree.h (struct c_declspecs): Add noreturn_p. * ginclude/stdnoreturn.h: New. * Makefile.in (USER_H): Add stdnoreturn.h. c-family: 2011-08-18 Joseph Myersjos...@codesourcery.com * c-common.c (c_common_reswords): Add _Noreturn. (keyword_is_function_specifier): Handle RID_NORETURN. * c-common.h (RID_NORETURN): New. testsuite: 2011-08-18 Joseph Myersjos...@codesourcery.com * gcc.dg/c1x-noreturn-1.c, gcc.dg/c1x-noreturn-2.c, gcc.dg/c1x-noreturn-3.c, gcc.dg/c1x-noreturn-4.c, gcc.dg/c1x-noreturn-5.c: New tests. Would it make any sense to accept _Noreturn as an alternative spelling for the __noreturn__ attribute, in case someone is using the non-underscore-wrapped variant? Thanks, Paolo
Re: C1X _Noreturn
On 08/24/2011 07:24 AM, Joseph S. Myers wrote: On Wed, 24 Aug 2011, Richard Sandiford wrote: Joseph S. Myersjos...@codesourcery.com writes: I didn't touch the USER_H definition in mips/t-sdemtk (so that target will not install this new header). The comment Remove stdarg.h and stddef.h from USER_H. suggests that maybe it should be added to that definition, but stdfix.h is also missing from that definition. As far as I know MIPS is no longer using the old SDE library and it is considered superseded by newlib, so perhaps that configuration (mips*-sde-elf* without newlib) should actually be deprecated/removed (and mipssde threads along with it). BTW, do you know whether the same applies to -mno-float, which at the moment is specific to sdemtk? That option was never really implemented, and just relied on the user being very, very careful. It would be nice to deprecate it at the same time. I don't know - Catherine, do you know if MIPS has ceased to use -mno-float along with replacing the SDE library with newlib? MIPS continues to use the -mno-float option. That should not be dperecated. As Joseph points out, the configuration for mips-sde-elf* without newlib is no longer in use and may be deprecated. Catherine
Re: C1X _Noreturn
On Wed, 24 Aug 2011, Paolo Bonzini wrote: Would it make any sense to accept _Noreturn as an alternative spelling for the __noreturn__ attribute, in case someone is using the non-underscore-wrapped variant? I suppose it might help some people use stdnoreturn.h, though I'm not really sure stdnoreturn.h is that useful. -- Joseph S. Myers jos...@codesourcery.com
Re: C1X _Noreturn
Joseph S. Myers jos...@codesourcery.com writes: As far as I know MIPS is no longer using the old SDE library and it is considered superseded by newlib, Hadn't realised that. so perhaps that configuration (mips*-sde-elf* without newlib) should actually be deprecated/removed (and mipssde threads along with it). Yeah, sounds like a good plan. Richard
Re: C1X _Noreturn
On Thu, 18 Aug 2011, Gabriel Dos Reis wrote:
On Thu, Aug 18, 2011 at 4:37 PM, Joseph S. Myers
jos...@codesourcery.com wrote:
The new keyword is C-only (C++0x has a different way of declaring
non-returning functions) and I did not try to make the header do
anything useful if included in C++ code.
I would suggest you don't define it all as macro when __cplusplus is defined.
This followup patch:
* stops stdnoreturn.h from defining the noreturn macro for C++, as
suggested;
* adds a pedwarn-if-pedantic for using _Noreturn outside C1X mode (not
formally required as it's in the reserved namespace, but still seems
useful and is similar to what's done with _Complex, for example);
* mentions _Noreturn in the syntax comments in the C parser.
Bootstrapped with no regressions on x86_64-unknown-linux-gnu. Applied
to mainline.
2011-08-19 Joseph Myers jos...@codesourcery.com
* c-decl.c (grokdeclarator): Diagnose _Noreturn for non-C1X if
pedantic.
* c-parser.c (c_parser_declspecs): Include _Noreturn in syntax
comment.
* ginclude/stdnoreturn.h (noreturn): Don't define for C++.
testsuite:
2011-08-19 Joseph Myers jos...@codesourcery.com
* gcc.dg/c90-noreturn-1.c, gcc.dg/c99-noreturn-1.c: New tests.
Index: gcc/ginclude/stdnoreturn.h
===
--- gcc/ginclude/stdnoreturn.h (revision 177894)
+++ gcc/ginclude/stdnoreturn.h (working copy)
@@ -26,6 +26,10 @@ see the files COPYING3 and COPYING.RUNTI
#ifndef _STDNORETURN_H
#define _STDNORETURN_H
+#ifndef __cplusplus
+
#define noreturn _Noreturn
+#endif
+
#endif /* stdnoreturn.h */
Index: gcc/testsuite/gcc.dg/c99-noreturn-1.c
===
--- gcc/testsuite/gcc.dg/c99-noreturn-1.c (revision 0)
+++ gcc/testsuite/gcc.dg/c99-noreturn-1.c (revision 0)
@@ -0,0 +1,5 @@
+/* Test _Noreturn not in C99. */
+/* { dg-do compile } */
+/* { dg-options -std=iso9899:1999 -pedantic-errors } */
+
+_Noreturn void f (void); /* { dg-error ISO C99 does not support '_Noreturn'
} */
Index: gcc/testsuite/gcc.dg/c90-noreturn-1.c
===
--- gcc/testsuite/gcc.dg/c90-noreturn-1.c (revision 0)
+++ gcc/testsuite/gcc.dg/c90-noreturn-1.c (revision 0)
@@ -0,0 +1,5 @@
+/* Test _Noreturn not in C90. */
+/* { dg-do compile } */
+/* { dg-options -std=iso9899:1990 -pedantic-errors } */
+
+_Noreturn void f (void); /* { dg-error ISO C90 does not support '_Noreturn'
} */
Index: gcc/c-decl.c
===
--- gcc/c-decl.c(revision 177894)
+++ gcc/c-decl.c(working copy)
@@ -5986,7 +5986,18 @@ grokdeclarator (const struct c_declarato
/* Record that the function is declared `inline'. */
DECL_DECLARED_INLINE_P (decl) = 1;
if (declspecs-noreturn_p)
- TREE_THIS_VOLATILE (decl) = 1;
+ {
+ if (!flag_isoc1x)
+ {
+ if (flag_isoc99)
+ pedwarn (loc, OPT_pedantic,
+ ISO C99 does not support %_Noreturn%);
+ else
+ pedwarn (loc, OPT_pedantic,
+ ISO C90 does not support %_Noreturn%);
+ }
+ TREE_THIS_VOLATILE (decl) = 1;
+ }
}
}
else
Index: gcc/c-parser.c
===
--- gcc/c-parser.c (revision 177894)
+++ gcc/c-parser.c (working copy)
@@ -1905,6 +1905,9 @@ c_parser_static_assert_declaration_no_se
C99 6.7.4:
function-specifier:
inline
+ _Noreturn
+
+ (_Noreturn is new in C1X.)
C90 6.5.2, C99 6.7.2:
type-specifier:
--
Joseph S. Myers
jos...@codesourcery.com
Re: C1X _Noreturn
Richard Sandiford rdsandif...@googlemail.com writes: so perhaps that configuration (mips*-sde-elf* without newlib) should actually be deprecated/removed (and mipssde threads along with it). Yeah, sounds like a good plan. Good to know :-) Could have saved me a little bit of work with the libgcc patches. Rainer -- - Rainer Orth, Center for Biotechnology, Bielefeld University
Re: C1X _Noreturn
On Thu, Aug 18, 2011 at 4:37 PM, Joseph S. Myers jos...@codesourcery.com wrote: The new keyword is C-only (C++0x has a different way of declaring non-returning functions) and I did not try to make the header do anything useful if included in C++ code. I would suggest you don't define it all as macro when __cplusplus is defined.
