gconv.h: fix build with GCC 6.3 or later
Commit Message
gconv.h is using a flex array to define the __gconv_info member in an
invalid way, causing the future GCC 6.3 (ie the gcc-6-branch) or the
future GCC 7 (ie the master branch) to issue an error:
| In file included from ../include/gconv.h:1:0,
| from ../sysdeps/unix/sysv/linux/_G_config.h:32,
| from ../libio/libio.h:31,
| from ../include/libio.h:4,
| from ../libio/stdio.h:74,
| from ../include/stdio.h:5,
| from test-math-isinff.cc:22:
| ../iconv/gconv.h:142:50: error: flexible array member '__gconv_info::__data' not at end of 'struct _IO_codecvt'
| In file included from ../include/libio.h:4:0,
| from ../libio/stdio.h:74,
| from ../include/stdio.h:5,
| from test-math-isinff.cc:22:
| ../libio/libio.h:211:14: note: next member '_G_iconv_t _IO_codecvt::__cd_out' declared here
| ../libio/libio.h:187:8: note: in the definition of 'struct _IO_codecvt'
| In file included from ../include/gconv.h:1:0,
| from ../sysdeps/unix/sysv/linux/_G_config.h:32,
| from ../libio/libio.h:31,
| from ../include/libio.h:4,
| from ../libio/stdio.h:74,
| from ../include/stdio.h:5,
| from test-math-isinff.cc:22:
| ../iconv/gconv.h:142:50: error: flexible array member '__gconv_info::__data' not at end of 'struct _IO_wide_data'
| In file included from ../include/libio.h:4:0,
| from ../libio/stdio.h:74,
| from ../include/stdio.h:5,
| from test-math-isinff.cc:22:
| ../libio/libio.h:211:14: note: next member '_G_iconv_t _IO_codecvt::__cd_out' declared here
| ../libio/libio.h:215:8: note: in the definition of 'struct _IO_wide_data'
This is basically a revert to the code from 15 years ago. More details
are available in the GCC bug:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78039
Changelog:
* iconv/gconv.h (__gconv_info): Define __data element using a
zero-length array.
---
ChangeLog | 5 +++++
iconv/gconv.h | 2 +-
2 files changed, 6 insertions(+), 1 deletion(-)
Comments
On Wed, 19 Oct 2016, Aurelien Jarno wrote:
> * iconv/gconv.h (__gconv_info): Define __data element using a
> zero-length array.
OK.
On 2016-11-05 21:52, Joseph Myers wrote:
> On Wed, 19 Oct 2016, Aurelien Jarno wrote:
>
> > * iconv/gconv.h (__gconv_info): Define __data element using a
> > zero-length array.
>
> OK.
Thanks for the review. Note that in the meantime GCC upstream reverted
the change from the GCC 6 branch, but it's still there in the trunk. I
have adjusted the commit message in consequence before committing it.
@@ -1,3 +1,8 @@
+2016-10-19 Aurelien Jarno <aurelien@aurel32.net>
+
+ * iconv/gconv.h (__gconv_info): Define __data element using a
+ zero-length array.
+
2016-10-19 Joseph Myers <joseph@codesourcery.com>
* math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
@@ -139,7 +139,7 @@ typedef struct __gconv_info
{
size_t __nsteps;
struct __gconv_step *__steps;
- __extension__ struct __gconv_step_data __data __flexarr;
+ __extension__ struct __gconv_step_data __data[0];
} *__gconv_t;
/* Transliteration using the locale's data. */