[thirdparty/gcc.git] / gcc / config / linux.h

/* Definitions for systems using the Linux kernel, with or without
   MMU, using ELF at the compiler level but possibly FLT for final
   linked executables and shared libraries in some no-MMU cases, and
   possibly with a choice of libc implementations.
   Copyright (C) 1995-2016 Free Software Foundation, Inc.
   Contributed by Eric Youngdale.
   Modified for stabs-in-ELF by H.J. Lu (hjl@lucon.org).

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  */

/* C libraries supported on Linux.  */
#ifdef SINGLE_LIBC
#define OPTION_GLIBC  (DEFAULT_LIBC == LIBC_GLIBC)
#define OPTION_UCLIBC (DEFAULT_LIBC == LIBC_UCLIBC)
#define OPTION_BIONIC (DEFAULT_LIBC == LIBC_BIONIC)
#undef OPTION_MUSL
#define OPTION_MUSL   (DEFAULT_LIBC == LIBC_MUSL)
#else
#define OPTION_GLIBC  (linux_libc == LIBC_GLIBC)
#define OPTION_UCLIBC (linux_libc == LIBC_UCLIBC)
#define OPTION_BIONIC (linux_libc == LIBC_BIONIC)
#undef OPTION_MUSL
#define OPTION_MUSL   (linux_libc == LIBC_MUSL)
#endif

#define GNU_USER_TARGET_OS_CPP_BUILTINS()			\
    do {							\
	if (OPTION_GLIBC)					\
	  builtin_define ("__gnu_linux__");			\
	builtin_define_std ("linux");				\
	builtin_define_std ("unix");				\
	builtin_assert ("system=linux");			\
	builtin_assert ("system=unix");				\
	builtin_assert ("system=posix");			\
    } while (0)

/* Determine which dynamic linker to use depending on whether GLIBC or
   uClibc or Bionic or musl is the default C library and whether
   -muclibc or -mglibc or -mbionic or -mmusl has been passed to change
   the default.  */

#define CHOOSE_DYNAMIC_LINKER1(LIBC1, LIBC2, LIBC3, LIBC4, LD1, LD2, LD3, LD4)	\
  "%{" LIBC2 ":" LD2 ";:%{" LIBC3 ":" LD3 ";:%{" LIBC4 ":" LD4 ";:" LD1 "}}}"

#if DEFAULT_LIBC == LIBC_GLIBC
#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
  CHOOSE_DYNAMIC_LINKER1 ("mglibc", "muclibc", "mbionic", "mmusl", G, U, B, M)
#elif DEFAULT_LIBC == LIBC_UCLIBC
#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
  CHOOSE_DYNAMIC_LINKER1 ("muclibc", "mglibc", "mbionic", "mmusl", U, G, B, M)
#elif DEFAULT_LIBC == LIBC_BIONIC
#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
  CHOOSE_DYNAMIC_LINKER1 ("mbionic", "mglibc", "muclibc", "mmusl", B, G, U, M)
#elif DEFAULT_LIBC == LIBC_MUSL
#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
  CHOOSE_DYNAMIC_LINKER1 ("mmusl", "mglibc", "muclibc", "mbionic", M, G, U, B)
#else
#error "Unsupported DEFAULT_LIBC"
#endif /* DEFAULT_LIBC */

/* For most targets the following definitions suffice;
   GLIBC_DYNAMIC_LINKER must be defined for each target using them, or
   GLIBC_DYNAMIC_LINKER32 and GLIBC_DYNAMIC_LINKER64 for targets
   supporting both 32-bit and 64-bit compilation.  */
#define UCLIBC_DYNAMIC_LINKER "/lib/ld-uClibc.so.0"
#define UCLIBC_DYNAMIC_LINKER32 "/lib/ld-uClibc.so.0"
#define UCLIBC_DYNAMIC_LINKER64 "/lib/ld64-uClibc.so.0"
#define UCLIBC_DYNAMIC_LINKERX32 "/lib/ldx32-uClibc.so.0"
#define BIONIC_DYNAMIC_LINKER "/system/bin/linker"
#define BIONIC_DYNAMIC_LINKER32 "/system/bin/linker"
#define BIONIC_DYNAMIC_LINKER64 "/system/bin/linker64"
#define BIONIC_DYNAMIC_LINKERX32 "/system/bin/linkerx32"
/* Should be redefined for each target that supports musl.  */
#define MUSL_DYNAMIC_LINKER "/dev/null"
#define MUSL_DYNAMIC_LINKER32 "/dev/null"
#define MUSL_DYNAMIC_LINKER64 "/dev/null"
#define MUSL_DYNAMIC_LINKERX32 "/dev/null"

#define GNU_USER_DYNAMIC_LINKER						\
  CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER,	\
			 BIONIC_DYNAMIC_LINKER, MUSL_DYNAMIC_LINKER)
#define GNU_USER_DYNAMIC_LINKER32					\
  CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER32, UCLIBC_DYNAMIC_LINKER32, \
			 BIONIC_DYNAMIC_LINKER32, MUSL_DYNAMIC_LINKER32)
#define GNU_USER_DYNAMIC_LINKER64					\
  CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER64, UCLIBC_DYNAMIC_LINKER64, \
			 BIONIC_DYNAMIC_LINKER64, MUSL_DYNAMIC_LINKER64)
#define GNU_USER_DYNAMIC_LINKERX32					\
  CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKERX32, UCLIBC_DYNAMIC_LINKERX32, \
			 BIONIC_DYNAMIC_LINKERX32, MUSL_DYNAMIC_LINKERX32)

/* Whether we have Bionic libc runtime */
#undef TARGET_HAS_BIONIC
#define TARGET_HAS_BIONIC (OPTION_BIONIC)

/* musl avoids problematic includes by rearranging the include directories.
 * Unfortunately, this is mostly duplicated from cppdefault.c */
#if DEFAULT_LIBC == LIBC_MUSL
#define INCLUDE_DEFAULTS_MUSL_GPP			\
    { GPLUSPLUS_INCLUDE_DIR, "G++", 1, 1,		\
      GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 },		\
    { GPLUSPLUS_TOOL_INCLUDE_DIR, "G++", 1, 1,		\
      GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 1 },		\
    { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1,	\
      GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 },

#ifdef LOCAL_INCLUDE_DIR
#define INCLUDE_DEFAULTS_MUSL_LOCAL			\
    { LOCAL_INCLUDE_DIR, 0, 0, 1, 1, 2 },		\
    { LOCAL_INCLUDE_DIR, 0, 0, 1, 1, 0 },
#else
#define INCLUDE_DEFAULTS_MUSL_LOCAL
#endif

#ifdef PREFIX_INCLUDE_DIR
#define INCLUDE_DEFAULTS_MUSL_PREFIX			\
    { PREFIX_INCLUDE_DIR, 0, 0, 1, 0, 0},
#else
#define INCLUDE_DEFAULTS_MUSL_PREFIX
#endif

#ifdef CROSS_INCLUDE_DIR
#define INCLUDE_DEFAULTS_MUSL_CROSS			\
    { CROSS_INCLUDE_DIR, "GCC", 0, 0, 0, 0},
#else
#define INCLUDE_DEFAULTS_MUSL_CROSS
#endif

#ifdef TOOL_INCLUDE_DIR
#define INCLUDE_DEFAULTS_MUSL_TOOL			\
    { TOOL_INCLUDE_DIR, "BINUTILS", 0, 1, 0, 0},
#else
#define INCLUDE_DEFAULTS_MUSL_TOOL
#endif

#ifdef NATIVE_SYSTEM_HEADER_DIR
#define INCLUDE_DEFAULTS_MUSL_NATIVE			\
    { NATIVE_SYSTEM_HEADER_DIR, 0, 0, 0, 1, 2 },	\
    { NATIVE_SYSTEM_HEADER_DIR, 0, 0, 0, 1, 0 },
#else
#define INCLUDE_DEFAULTS_MUSL_NATIVE
#endif

#if defined (CROSS_DIRECTORY_STRUCTURE) && !defined (TARGET_SYSTEM_ROOT)
# undef INCLUDE_DEFAULTS_MUSL_LOCAL
# define INCLUDE_DEFAULTS_MUSL_LOCAL
# undef INCLUDE_DEFAULTS_MUSL_NATIVE
# define INCLUDE_DEFAULTS_MUSL_NATIVE
#else
# undef INCLUDE_DEFAULTS_MUSL_CROSS
# define INCLUDE_DEFAULTS_MUSL_CROSS
#endif

#undef INCLUDE_DEFAULTS
#define INCLUDE_DEFAULTS				\
  {							\
    INCLUDE_DEFAULTS_MUSL_GPP				\
    INCLUDE_DEFAULTS_MUSL_LOCAL				\
    INCLUDE_DEFAULTS_MUSL_PREFIX			\
    INCLUDE_DEFAULTS_MUSL_CROSS				\
    INCLUDE_DEFAULTS_MUSL_TOOL				\
    INCLUDE_DEFAULTS_MUSL_NATIVE			\
    { GCC_INCLUDE_DIR, "GCC", 0, 1, 0, 0 },		\
    { 0, 0, 0, 0, 0, 0 }				\
  }
#endif

#if (DEFAULT_LIBC == LIBC_UCLIBC) && defined (SINGLE_LIBC) /* uClinux */
/* This is a *uclinux* target.  We don't define below macros to normal linux
   versions, because doing so would require *uclinux* targets to include
   linux.c, linux-protos.h, linux.opt, etc.  We could, alternatively, add
   these files to *uclinux* targets, but that would only pollute option list
   (add -mglibc, etc.) without adding any useful support.  */

/* Define TARGET_LIBC_HAS_FUNCTION for *uclinux* targets to
   no_c99_libc_has_function, because uclibc does not, normally, have
   c99 runtime.  If, in special cases, uclibc does have c99 runtime,
   this should be defined to a new hook.  Also please note that for targets
   like *-linux-uclibc that similar check will also need to be added to
   linux_libc_has_function.  */
# undef TARGET_LIBC_HAS_FUNCTION
# define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function

#else /* !uClinux, i.e., normal Linux */

/* Determine what functions are present at the runtime;
   this includes full c99 runtime and sincos.  */
# undef TARGET_LIBC_HAS_FUNCTION
# define TARGET_LIBC_HAS_FUNCTION linux_libc_has_function

#endif
Commit	Line	Data
deb14f24	1	/* Definitions for systems using the Linux kernel, with or without
	2	MMU, using ELF at the compiler level but possibly FLT for final
	3	linked executables and shared libraries in some no-MMU cases, and
	4	possibly with a choice of libc implementations.
f1717362	5	Copyright (C) 1995-2016 Free Software Foundation, Inc.
b80b8662	6	Contributed by Eric Youngdale.
997d68fe	7	Modified for stabs-in-ELF by H.J. Lu (hjl@lucon.org).
b80b8662	8
9a4d577b	9	This file is part of GCC.
b80b8662	10
9a4d577b	11	GCC is free software; you can redistribute it and/or modify
b80b8662	12	it under the terms of the GNU General Public License as published by
038d1e19	13	the Free Software Foundation; either version 3, or (at your option)
b80b8662	14	any later version.
b80b8662	15
9a4d577b	16	GCC is distributed in the hope that it will be useful,
b80b8662	17	but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	19	GNU General Public License for more details.
	20
6bc9506f	21	Under Section 7 of GPL version 3, you are granted additional
	22	permissions described in the GCC Runtime Library Exception, version
	23	3.1, as published by the Free Software Foundation.
	24
	25	You should have received a copy of the GNU General Public License and
	26	a copy of the GCC Runtime Library Exception along with this program;
	27	see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
038d1e19	28	<http://www.gnu.org/licenses/>. */
b80b8662	29
66fd9df9	30	/* C libraries supported on Linux. */
d9993a19	31	#ifdef SINGLE_LIBC
	32	#define OPTION_GLIBC (DEFAULT_LIBC == LIBC_GLIBC)
	33	#define OPTION_UCLIBC (DEFAULT_LIBC == LIBC_UCLIBC)
	34	#define OPTION_BIONIC (DEFAULT_LIBC == LIBC_BIONIC)
f2d678af	35	#undef OPTION_MUSL
a9173cea	36	#define OPTION_MUSL (DEFAULT_LIBC == LIBC_MUSL)
d9993a19	37	#else
66fd9df9	38	#define OPTION_GLIBC (linux_libc == LIBC_GLIBC)
	39	#define OPTION_UCLIBC (linux_libc == LIBC_UCLIBC)
	40	#define OPTION_BIONIC (linux_libc == LIBC_BIONIC)
f2d678af	41	#undef OPTION_MUSL
a9173cea	42	#define OPTION_MUSL (linux_libc == LIBC_MUSL)
d9993a19	43	#endif
66fd9df9	44
493a87fa	45	#define GNU_USER_TARGET_OS_CPP_BUILTINS() \
bcc76966	46	do { \
66fd9df9	47	if (OPTION_GLIBC) \
66fd9df9	48	builtin_define ("__gnu_linux__"); \
bcc76966	49	builtin_define_std ("linux"); \
	50	builtin_define_std ("unix"); \
	51	builtin_assert ("system=linux"); \
	52	builtin_assert ("system=unix"); \
	53	builtin_assert ("system=posix"); \
	54	} while (0)
	55
ee085235	56	/* Determine which dynamic linker to use depending on whether GLIBC or
a9173cea	57	uClibc or Bionic or musl is the default C library and whether
	58	-muclibc or -mglibc or -mbionic or -mmusl has been passed to change
	59	the default. */
66fd9df9	60
a9173cea	61	#define CHOOSE_DYNAMIC_LINKER1(LIBC1, LIBC2, LIBC3, LIBC4, LD1, LD2, LD3, LD4) \
a9173cea	62	"%{" LIBC2 ":" LD2 ";:%{" LIBC3 ":" LD3 ";:%{" LIBC4 ":" LD4 ";:" LD1 "}}}"
66fd9df9	63
66fd9df9	64	#if DEFAULT_LIBC == LIBC_GLIBC
a9173cea	65	#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
a9173cea	66	CHOOSE_DYNAMIC_LINKER1 ("mglibc", "muclibc", "mbionic", "mmusl", G, U, B, M)
66fd9df9	67	#elif DEFAULT_LIBC == LIBC_UCLIBC
a9173cea	68	#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
a9173cea	69	CHOOSE_DYNAMIC_LINKER1 ("muclibc", "mglibc", "mbionic", "mmusl", U, G, B, M)
66fd9df9	70	#elif DEFAULT_LIBC == LIBC_BIONIC
a9173cea	71	#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
	72	CHOOSE_DYNAMIC_LINKER1 ("mbionic", "mglibc", "muclibc", "mmusl", B, G, U, M)
	73	#elif DEFAULT_LIBC == LIBC_MUSL
	74	#define CHOOSE_DYNAMIC_LINKER(G, U, B, M) \
	75	CHOOSE_DYNAMIC_LINKER1 ("mmusl", "mglibc", "muclibc", "mbionic", M, G, U, B)
ee085235	76	#else
66fd9df9	77	#error "Unsupported DEFAULT_LIBC"
66fd9df9	78	#endif /* DEFAULT_LIBC */
ee085235	79
c490c13b	80	/* For most targets the following definitions suffice;
	81	GLIBC_DYNAMIC_LINKER must be defined for each target using them, or
	82	GLIBC_DYNAMIC_LINKER32 and GLIBC_DYNAMIC_LINKER64 for targets
	83	supporting both 32-bit and 64-bit compilation. */
ee085235	84	#define UCLIBC_DYNAMIC_LINKER "/lib/ld-uClibc.so.0"
c490c13b	85	#define UCLIBC_DYNAMIC_LINKER32 "/lib/ld-uClibc.so.0"
c490c13b	86	#define UCLIBC_DYNAMIC_LINKER64 "/lib/ld64-uClibc.so.0"
596b2ba3	87	#define UCLIBC_DYNAMIC_LINKERX32 "/lib/ldx32-uClibc.so.0"
66fd9df9	88	#define BIONIC_DYNAMIC_LINKER "/system/bin/linker"
	89	#define BIONIC_DYNAMIC_LINKER32 "/system/bin/linker"
	90	#define BIONIC_DYNAMIC_LINKER64 "/system/bin/linker64"
596b2ba3	91	#define BIONIC_DYNAMIC_LINKERX32 "/system/bin/linkerx32"
a9173cea	92	/* Should be redefined for each target that supports musl. */
	93	#define MUSL_DYNAMIC_LINKER "/dev/null"
	94	#define MUSL_DYNAMIC_LINKER32 "/dev/null"
	95	#define MUSL_DYNAMIC_LINKER64 "/dev/null"
	96	#define MUSL_DYNAMIC_LINKERX32 "/dev/null"
66fd9df9	97
493a87fa	98	#define GNU_USER_DYNAMIC_LINKER \
66fd9df9	99	CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER, \
a9173cea	100	BIONIC_DYNAMIC_LINKER, MUSL_DYNAMIC_LINKER)
493a87fa	101	#define GNU_USER_DYNAMIC_LINKER32 \
66fd9df9	102	CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER32, UCLIBC_DYNAMIC_LINKER32, \
a9173cea	103	BIONIC_DYNAMIC_LINKER32, MUSL_DYNAMIC_LINKER32)
493a87fa	104	#define GNU_USER_DYNAMIC_LINKER64 \
66fd9df9	105	CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKER64, UCLIBC_DYNAMIC_LINKER64, \
a9173cea	106	BIONIC_DYNAMIC_LINKER64, MUSL_DYNAMIC_LINKER64)
596b2ba3	107	#define GNU_USER_DYNAMIC_LINKERX32 \
596b2ba3	108	CHOOSE_DYNAMIC_LINKER (GLIBC_DYNAMIC_LINKERX32, UCLIBC_DYNAMIC_LINKERX32, \
a9173cea	109	BIONIC_DYNAMIC_LINKERX32, MUSL_DYNAMIC_LINKERX32)
ee085235	110
05c1aa95	111	/* Whether we have Bionic libc runtime */
	112	#undef TARGET_HAS_BIONIC
	113	#define TARGET_HAS_BIONIC (OPTION_BIONIC)
30f690e0	114
a9173cea	115	/* musl avoids problematic includes by rearranging the include directories.
	116	* Unfortunately, this is mostly duplicated from cppdefault.c */
	117	#if DEFAULT_LIBC == LIBC_MUSL
	118	#define INCLUDE_DEFAULTS_MUSL_GPP \
	119	{ GPLUSPLUS_INCLUDE_DIR, "G++", 1, 1, \
	120	GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 }, \
	121	{ GPLUSPLUS_TOOL_INCLUDE_DIR, "G++", 1, 1, \
	122	GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 1 }, \
	123	{ GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1, \
	124	GPLUSPLUS_INCLUDE_DIR_ADD_SYSROOT, 0 },
	125
	126	#ifdef LOCAL_INCLUDE_DIR
	127	#define INCLUDE_DEFAULTS_MUSL_LOCAL \
	128	{ LOCAL_INCLUDE_DIR, 0, 0, 1, 1, 2 }, \
	129	{ LOCAL_INCLUDE_DIR, 0, 0, 1, 1, 0 },
	130	#else
	131	#define INCLUDE_DEFAULTS_MUSL_LOCAL
	132	#endif
	133
	134	#ifdef PREFIX_INCLUDE_DIR
	135	#define INCLUDE_DEFAULTS_MUSL_PREFIX \
	136	{ PREFIX_INCLUDE_DIR, 0, 0, 1, 0, 0},
	137	#else
	138	#define INCLUDE_DEFAULTS_MUSL_PREFIX
	139	#endif
	140
	141	#ifdef CROSS_INCLUDE_DIR
	142	#define INCLUDE_DEFAULTS_MUSL_CROSS \
	143	{ CROSS_INCLUDE_DIR, "GCC", 0, 0, 0, 0},
	144	#else
	145	#define INCLUDE_DEFAULTS_MUSL_CROSS
	146	#endif
	147
	148	#ifdef TOOL_INCLUDE_DIR
	149	#define INCLUDE_DEFAULTS_MUSL_TOOL \
	150	{ TOOL_INCLUDE_DIR, "BINUTILS", 0, 1, 0, 0},
	151	#else
	152	#define INCLUDE_DEFAULTS_MUSL_TOOL
	153	#endif
	154
	155	#ifdef NATIVE_SYSTEM_HEADER_DIR
	156	#define INCLUDE_DEFAULTS_MUSL_NATIVE \
	157	{ NATIVE_SYSTEM_HEADER_DIR, 0, 0, 0, 1, 2 }, \
	158	{ NATIVE_SYSTEM_HEADER_DIR, 0, 0, 0, 1, 0 },
	159	#else
	160	#define INCLUDE_DEFAULTS_MUSL_NATIVE
	161	#endif
	162
	163	#if defined (CROSS_DIRECTORY_STRUCTURE) && !defined (TARGET_SYSTEM_ROOT)
	164	# undef INCLUDE_DEFAULTS_MUSL_LOCAL
	165	# define INCLUDE_DEFAULTS_MUSL_LOCAL
	166	# undef INCLUDE_DEFAULTS_MUSL_NATIVE
	167	# define INCLUDE_DEFAULTS_MUSL_NATIVE
	168	#else
	169	# undef INCLUDE_DEFAULTS_MUSL_CROSS
	170	# define INCLUDE_DEFAULTS_MUSL_CROSS
	171	#endif
	172
	173	#undef INCLUDE_DEFAULTS
	174	#define INCLUDE_DEFAULTS \
	175	{ \
	176	INCLUDE_DEFAULTS_MUSL_GPP \
599e4bed	177	INCLUDE_DEFAULTS_MUSL_LOCAL \
a9173cea	178	INCLUDE_DEFAULTS_MUSL_PREFIX \
	179	INCLUDE_DEFAULTS_MUSL_CROSS \
	180	INCLUDE_DEFAULTS_MUSL_TOOL \
	181	INCLUDE_DEFAULTS_MUSL_NATIVE \
	182	{ GCC_INCLUDE_DIR, "GCC", 0, 1, 0, 0 }, \
	183	{ 0, 0, 0, 0, 0, 0 } \
	184	}
	185	#endif
	186
89ac5e5b	187	#if (DEFAULT_LIBC == LIBC_UCLIBC) && defined (SINGLE_LIBC) /* uClinux */
	188	/* This is a uclinux target. We don't define below macros to normal linux
	189	versions, because doing so would require uclinux targets to include
	190	linux.c, linux-protos.h, linux.opt, etc. We could, alternatively, add
	191	these files to uclinux targets, but that would only pollute option list
	192	(add -mglibc, etc.) without adding any useful support. */
	193
	194	/* Define TARGET_LIBC_HAS_FUNCTION for uclinux targets to
	195	no_c99_libc_has_function, because uclibc does not, normally, have
	196	c99 runtime. If, in special cases, uclibc does have c99 runtime,
	197	this should be defined to a new hook. Also please note that for targets
	198	like *-linux-uclibc that similar check will also need to be added to
	199	linux_libc_has_function. */
	200	# undef TARGET_LIBC_HAS_FUNCTION
	201	# define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function
	202
	203	#else /* !uClinux, i.e., normal Linux */
	204
30f690e0	205	/* Determine what functions are present at the runtime;
30f690e0	206	this includes full c99 runtime and sincos. */
89ac5e5b	207	# undef TARGET_LIBC_HAS_FUNCTION
	208	# define TARGET_LIBC_HAS_FUNCTION linux_libc_has_function
	209
	210	#endif