-std=c1x

GCC 4.6

-std=c11

GCC 4.7

_Static_assert

GCC 4.6

static_assert in assert.h

Library issue (glibc 2.16)

Typedef redefinition

GCC 4.6

Anonymous struct and union

GCC 4.6

New macros in float.h

GCC 4.6

_Alignas, _Alignof, max_align_t, stdalign.h

GCC 4.7

_Atomic

-

Atomic operations

GCC 4.7

Macros for Complex values

GCC 4.7 + Library issue (glibc 2.16)

Unicode strings

GCC 4.7

uchar.h

Library issue (glibc 2.16)

_Noreturn, stdnoreturn.h

GCC 4.7

_Generic

-

__STDC_VERSION__ == 201112L

GCC 4.7

Analyzability (Annex L) [Optional]

Library issue

Bounds-checking (Annex K) [Optional]

Library issue

Threading [Optional]

Library issue/?

Remove gets

Library issue (glibc 2.16)

struct timespec, timespec_get

Library issue (glibc 2.16)

at_quick_exit, quick_exit

Library issue (glibc 2.16)

aligned_alloc

Library issue (glibc 2.16)

fopen mode "x"

Library issue (glibc)