gcc:
	PR target/20353
	PR target/24578
	PR target/24837
	* config/linux.opt: New file.
	* config/linux.h (CHOOSE_DYNAMIC_LINKER, UCLIBC_DYNAMIC_LINKER,
	LINUX_DYNAMIC_LINKER): Define.
	(TARGET_C99_FUNCTIONS): Define depending on TARGET_GLIBC.
	* config.gcc (*-*-linux*): Define extra_options.
	(*-*-*uclibc*): Define UCLIBC_DEFAULT.
	(arm*-*-linux-gnueabi): Change to arm*-*-linux-*eabi.
	* config/arm/linux-eabi.h (LINUX_TARGET_INTERPRETER): Change to
	GLIBC_DYNAMIC_LINKER.
	* config/arm/linux-elf.h (LINUX_TARGET_INTERPRETER): Likewise.
	(LINUX_TARGET_LINK_SPEC): Use LINUX_DYNAMIC_LINKER.
	* config/mips/linux.h (GLIBC_DYNAMIC_LINKER): Define.
	(LINK_SPEC): Use LINUX_DYNAMIC_LINKER.
	* doc/invoke.texi (GNU/Linux Options): New section.

gcc/testsuite:
	* gcc.dg/builtins-config.h (HAVE_C99_RUNTIME): Don't define if
	__UCLIBC__ is defined.

libstdc++-v3:
	PR libstdc++/14939
	* config/os/uclibc/ctype_base.h, config/os/uclibc/ctype_inline.h,
	config/os/uclibc/ctype_noninline.h, config/os/uclibc/os_defines.h:
	New.
	* acinclude.m4 (GLIBCXX_CONFIGURE): Test whether using uClibc.
	* configure.host: Use os/uclibc for uClibc.
	* crossconfig.m4 (*-linux*): Use link tests.  Don't hardcode
	presence of math functions.
	* configure: Regenerate.

From-SVN: r111160