gconv.h is using a flex array to define the __gconv_info member in an
invalid way, causing GCC 7 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.
0623b9e6a9