Jeff?

On Jan 24 16:05, Thomas Preudhomme wrote:
> Hi,
> 
> At the moment when targeting bare-metal targets or systems without
> definition for the locking primitives newlib, uses dummy empty macros. This
> has the advantage of reduced size and faster implementation but does not
> allow the application to retarget the locking routines. Retargeting is
> useful for a single toolchain to support multiple systems since then it's
> only at link time that you know which system you are targeting.
> 
> This patch adds a new configure option --enable-newlib-retargetable-locking
> to use dummy empty functions instead of dummy empty macros. The default is
> to keep the current behavior to not have any size or speed impact on targets
> not interested in this feature. To allow for any size of lock, the _LOCK_T
> type is changed into pointer to struct _lock and the _init function are
> tasked with allocating the locks. The platform being targeted must provide
> the static locks. A dummy implementation of the locking routines and static
> lock is provided for single-threaded applications to link successfully out
> of the box.
> 
> To ensure that the behavior is consistent (either no locking whatsoever or
> working locking), the dummy implementation is strongly defined such that a
> partial retargeting will cause a doubly defined link error. Indeed, the
> linker will only pull in the file providing the dummy implementation if it
> cannot find an implementation for one of the routine or lock.
> 
> Testing: I've built a simple test program that calls malloc and free with
> all the locking function defined in the same file. Running into a debugger
> with breakpoints on the function shows that they are indeed called. Newlib
> testsuite (the 30 tests that run wich check-target-newlib from GCC) also
> comes back clean.
> 
> Is this ok for master branch?
> 
> Best regards,
> 
> Thomas

> diff --git a/newlib/configure b/newlib/configure
> index 2ac07fe06bfc795d94ba36d0061e4f8135146125..de28c25b3c4aaeed14b6d0ee8354fdd5c5c3115a 100755
> --- a/newlib/configure
> +++ b/newlib/configure
> @@ -802,6 +802,7 @@ enable_newlib_nano_malloc
>  enable_newlib_unbuf_stream_opt
>  enable_lite_exit
>  enable_newlib_nano_formatted_io
> +enable_newlib_retargetable_locking
>  enable_multilib
>  enable_target_optspace
>  enable_malloc_debugging
> @@ -1473,6 +1474,7 @@ Optional Features:
>    --disable-newlib-unbuf-stream-opt    disable unbuffered stream optimization in streamio
>    --enable-lite-exit	enable light weight exit
>    --enable-newlib-nano-formatted-io    Use nano version formatted IO
> +  --enable-newlib-retargetable-locking    Allow locking routines to be retargeted at link time
>    --enable-multilib         build many library versions (default)
>    --enable-target-optspace  optimize for space
>    --enable-malloc-debugging indicate malloc debugging requested
> @@ -2474,6 +2476,18 @@ else
>  fi
>  
>  
> +# Check whether --enable-newlib-retargetable-locking was given.
> +if test "${enable_newlib_retargetable_locking+set}" = set; then :
> +  enableval=$enable_newlib_retargetable_locking; case "${enableval}" in
> +   yes) newlib_retargetable_locking=yes ;;
> +   no)  newlib_retargetable_locking=no ;;
> +   *) as_fn_error $? "bad value ${enableval} for newlib-retargetable-locking" "$LINENO" 5 ;;
> + esac
> +else
> +  newlib_retargetable_locking=no
> +fi
> +
> +
>  
>  # Make sure we can run config.sub.
>  $SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
> @@ -11780,7 +11794,7 @@ else
>    lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
>    lt_status=$lt_dlunknown
>    cat > conftest.$ac_ext <<_LT_EOF
> -#line 11783 "configure"
> +#line 11797 "configure"
>  #include "confdefs.h"
>  
>  #if HAVE_DLFCN_H
> @@ -11886,7 +11900,7 @@ else
>    lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
>    lt_status=$lt_dlunknown
>    cat > conftest.$ac_ext <<_LT_EOF
> -#line 11889 "configure"
> +#line 11903 "configure"
>  #include "confdefs.h"
>  
>  #if HAVE_DLFCN_H
> @@ -12455,6 +12469,13 @@ _ACEOF
>  
>  fi
>  
> +if test "${newlib_retargetable_locking}" = "yes"; then
> +cat >>confdefs.h <<_ACEOF
> +#define _RETARGETABLE_LOCKING 1
> +_ACEOF
> +
> +fi
> +
>  
>  if test "x${iconv_encodings}" != "x" \
>     || test "x${iconv_to_encodings}" != "x" \
> diff --git a/newlib/configure.in b/newlib/configure.in
> index bfaf038c7f495d32d05ae8caff0172f464895ffe..354c07ca580edf75da59fb858ca2c434e0b1a4e9 100644
> --- a/newlib/configure.in
> +++ b/newlib/configure.in
> @@ -218,6 +218,17 @@ AC_ARG_ENABLE(newlib_nano_formatted_io,
>     *) AC_MSG_ERROR(bad value ${enableval} for newlib-nano-formatted-io) ;;
>   esac],[newlib_nano_formatted_io=no])
>  
> +dnl Support --enable-retargetable-locking
> +dnl This option is also read in libc/configure.in.  It is repeated
> +dnl here so that it shows up in the help text.
> +AC_ARG_ENABLE(newlib-retargetable-locking,
> +[  --enable-newlib-retargetable-locking    Allow locking routines to be retargeted at link time],
> +[case "${enableval}" in
> +   yes) newlib_retargetable_locking=yes ;;
> +   no)  newlib_retargetable_locking=no ;;
> +   *) AC_MSG_ERROR(bad value ${enableval} for newlib-retargetable-locking) ;;
> + esac],[newlib_retargetable_locking=no])
> +
>  NEWLIB_CONFIGURE(.)
>  
>  dnl We have to enable libtool after NEWLIB_CONFIGURE because if we try and
> @@ -458,6 +469,10 @@ if test "${newlib_nano_formatted_io}" = "yes"; then
>  AC_DEFINE_UNQUOTED(_NANO_FORMATTED_IO)
>  fi
>  
> +if test "${newlib_retargetable_locking}" = "yes"; then
> +AC_DEFINE_UNQUOTED(_RETARGETABLE_LOCKING)
> +fi
> +
>  dnl
>  dnl Parse --enable-newlib-iconv-encodings option argument
>  dnl
> diff --git a/newlib/libc/configure b/newlib/libc/configure
> index 4dc4d1bf703f388ecd3b4e0d8bef6786f7995021..dabe44fd98d74a2e029a22a217953dd52575736f 100755
> --- a/newlib/libc/configure
> +++ b/newlib/libc/configure
> @@ -751,6 +751,8 @@ build
>  newlib_basedir
>  MAY_SUPPLY_SYSCALLS_FALSE
>  MAY_SUPPLY_SYSCALLS_TRUE
> +NEWLIB_RETARGETABLE_LOCKING_FALSE
> +NEWLIB_RETARGETABLE_LOCKING_TRUE
>  NEWLIB_NANO_FORMATTED_IO_FALSE
>  NEWLIB_NANO_FORMATTED_IO_TRUE
>  target_alias
> @@ -797,6 +799,7 @@ enable_option_checking
>  enable_newlib_io_pos_args
>  enable_newlib_nano_malloc
>  enable_newlib_nano_formatted_io
> +enable_newlib_retargetable_locking
>  enable_multilib
>  enable_target_optspace
>  enable_malloc_debugging
> @@ -1448,6 +1451,7 @@ Optional Features:
>    --enable-newlib-io-pos-args enable printf-family positional arg support
>    --enable-newlib-nano-malloc    Use small-footprint nano-malloc implementation
>    --enable-newlib-nano-formatted-io    Use small-footprint nano-formatted-IO implementation
> +  --enable-newlib-retargetable-locking    Allow locking routines to be retargeted at link time
>    --enable-multilib         build many library versions (default)
>    --enable-target-optspace  optimize for space
>    --enable-malloc-debugging indicate malloc debugging requested
> @@ -2252,6 +2256,26 @@ else
>  fi
>  
>  
> +# Check whether --enable-newlib-retargetable-locking was given.
> +if test "${enable_newlib_retargetable_locking+set}" = set; then :
> +  enableval=$enable_newlib_retargetable_locking; case "${enableval}" in
> +   yes) newlib_retargetable_locking=yes ;;
> +   no)  newlib_retargetable_lock=no ;;
> +   *) as_fn_error $? "bad value ${enableval} for newlib-retargetable-locking" "$LINENO" 5 ;;
> + esac
> +else
> +  newlib_retargetable_locking=no
> +fi
> +
> + if test x$newlib_retargetable_locking = xyes; then
> +  NEWLIB_RETARGETABLE_LOCKING_TRUE=
> +  NEWLIB_RETARGETABLE_LOCKING_FALSE='#'
> +else
> +  NEWLIB_RETARGETABLE_LOCKING_TRUE='#'
> +  NEWLIB_RETARGETABLE_LOCKING_FALSE=
> +fi
> +
> +
>  
>  # Make sure we can run config.sub.
>  $SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
> @@ -11525,7 +11549,7 @@ else
>    lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
>    lt_status=$lt_dlunknown
>    cat > conftest.$ac_ext <<_LT_EOF
> -#line 11528 "configure"
> +#line 11552 "configure"
>  #include "confdefs.h"
>  
>  #if HAVE_DLFCN_H
> @@ -11631,7 +11655,7 @@ else
>    lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
>    lt_status=$lt_dlunknown
>    cat > conftest.$ac_ext <<_LT_EOF
> -#line 11634 "configure"
> +#line 11658 "configure"
>  #include "confdefs.h"
>  
>  #if HAVE_DLFCN_H
> @@ -12248,6 +12272,10 @@ if test -z "${NEWLIB_NANO_FORMATTED_IO_TRUE}" && test -z "${NEWLIB_NANO_FORMATTE
>    as_fn_error $? "conditional \"NEWLIB_NANO_FORMATTED_IO\" was never defined.
>  Usually this means the macro was only invoked conditionally." "$LINENO" 5
>  fi
> +if test -z "${NEWLIB_RETARGETABLE_LOCKING_TRUE}" && test -z "${NEWLIB_RETARGETABLE_LOCKING_FALSE}"; then
> +  as_fn_error $? "conditional \"NEWLIB_RETARGETABLE_LOCKING\" was never defined.
> +Usually this means the macro was only invoked conditionally." "$LINENO" 5
> +fi
>  if test -z "${MAY_SUPPLY_SYSCALLS_TRUE}" && test -z "${MAY_SUPPLY_SYSCALLS_FALSE}"; then
>    as_fn_error $? "conditional \"MAY_SUPPLY_SYSCALLS\" was never defined.
>  Usually this means the macro was only invoked conditionally." "$LINENO" 5
> diff --git a/newlib/libc/configure.in b/newlib/libc/configure.in
> index 0a7bb8815be44fb1e92f753fa2c8df2a31b95f94..ac25a3933c4a4794f3cfe291e0275d0ed001b96a 100644
> --- a/newlib/libc/configure.in
> +++ b/newlib/libc/configure.in
> @@ -36,6 +36,16 @@ AC_ARG_ENABLE(newlib_nano_formatted_io,
>   esac],[newlib_nano_formatted_io=no])
>  AM_CONDITIONAL(NEWLIB_NANO_FORMATTED_IO, test x$newlib_nano_formatted_io = xyes)
>  
> +dnl Support --enable-retargetable-locking used by libc/sys
> +AC_ARG_ENABLE(newlib-retargetable-locking,
> +[  --enable-newlib-retargetable-locking    Allow locking routines to be retargeted at link time],
> +[case "${enableval}" in
> +   yes) newlib_retargetable_locking=yes ;;
> +   no)  newlib_retargetable_lock=no ;;
> +   *) AC_MSG_ERROR(bad value ${enableval} for newlib-retargetable-locking) ;;
> + esac],[newlib_retargetable_locking=no])
> +AM_CONDITIONAL(NEWLIB_RETARGETABLE_LOCKING, test x$newlib_retargetable_locking = xyes)
> +
>  NEWLIB_CONFIGURE(..)
>  
>  AM_CONDITIONAL(NEWLIB_NANO_MALLOC, test x$newlib_nano_malloc = xyes)
> diff --git a/newlib/libc/include/sys/lock.h b/newlib/libc/include/sys/lock.h
> index 9075e35c9179968031010432515e3a845ff6ca8d..9a8e2528c79a89d5807da8c4bb0e65151870bf42 100644
> --- a/newlib/libc/include/sys/lock.h
> +++ b/newlib/libc/include/sys/lock.h
> @@ -3,10 +3,13 @@
>  
>  /* dummy lock routines for single-threaded aps */
>  
> +#include <newlib.h>
> +#include <_ansi.h>
> +
> +#ifndef _RETARGETABLE_LOCKING
> +
>  typedef int _LOCK_T;
>  typedef int _LOCK_RECURSIVE_T;
> - 
> -#include <_ansi.h>
>  
>  #define __LOCK_INIT(class,lock) static int lock = 0;
>  #define __LOCK_INIT_RECURSIVE(class,lock) static int lock = 0;
> @@ -21,4 +24,46 @@ typedef int _LOCK_RECURSIVE_T;
>  #define __lock_release(lock) (_CAST_VOID 0)
>  #define __lock_release_recursive(lock) (_CAST_VOID 0)
>  
> +#else
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +struct _lock;
> +typedef struct _lock * _LOCK_T;
> +#define _LOCK_RECURSIVE_T _LOCK_T
> +
> +#define __LOCK_INIT(class,lock) extern struct _lock _lock_ ## lock; \
> +	class _LOCK_T lock = &_lock_ ## lock
> +#define __LOCK_INIT_RECURSIVE(class,lock) __LOCK_INIT(class,lock)
> +
> +extern void __retarget_lock_init(_LOCK_T *lock);
> +#define __lock_init(lock) __retarget_lock_init(&lock)
> +extern void __retarget_lock_init_recursive(_LOCK_T *lock);
> +#define __lock_init_recursive(lock) __retarget_lock_init_recursive(&lock)
> +extern void __retarget_lock_close(_LOCK_T lock);
> +#define __lock_close(lock) __retarget_lock_close(lock)
> +extern void __retarget_lock_close_recursive(_LOCK_T lock);
> +#define __lock_close_recursive(lock) __retarget_lock_close_recursive(lock)
> +extern void __retarget_lock_acquire(_LOCK_T lock);
> +#define __lock_acquire(lock) __retarget_lock_acquire(lock)
> +extern void __retarget_lock_acquire_recursive(_LOCK_T lock);
> +#define __lock_acquire_recursive(lock) __retarget_lock_acquire_recursive(lock)
> +extern int __retarget_lock_try_acquire(_LOCK_T lock);
> +#define __lock_try_acquire(lock) __retarget_lock_try_acquire(lock)
> +extern int __retarget_lock_try_acquire_recursive(_LOCK_T lock);
> +#define __lock_try_acquire_recursive(lock) \
> +  __retarget_lock_try_acquire_recursive(lock)
> +extern void __retarget_lock_release(_LOCK_T lock);
> +#define __lock_release(lock) __retarget_lock_release(lock)
> +extern void __retarget_lock_release_recursive(_LOCK_T lock);
> +#define __lock_release_recursive(lock) __retarget_lock_release_recursive(lock)
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif /* _RETARGETABLE_LOCKING */
> +
>  #endif /* __SYS_LOCK_H__ */
> diff --git a/newlib/libc/misc/Makefile.am b/newlib/libc/misc/Makefile.am
> index 3fe8e55f53ca87ba55f3a676b213e55fa66e77aa..7571ef26335c053315ad3f3df428a4742a9cf368 100644
> --- a/newlib/libc/misc/Makefile.am
> +++ b/newlib/libc/misc/Makefile.am
> @@ -6,6 +6,11 @@ INCLUDES = $(NEWLIB_CFLAGS) $(CROSS_CFLAGS) $(TARGET_CFLAGS)
>  
>  LIB_SOURCES = __dprintf.c unctrl.c ffs.c init.c fini.c
>  
> +if NEWLIB_RETARGETABLE_LOCKING
> +LIB_SOURCES += \
> +	lock.c
> +endif
> +
>  libmisc_la_LDFLAGS = -Xcompiler -nostdlib
>  
>  if USE_LIBTOOL
> @@ -21,5 +26,5 @@ endif # USE_LIBTOOL
>  
>  include $(srcdir)/../../Makefile.shared
>  
> -CHEWOUT_FILES = unctrl.def ffs.def
> +CHEWOUT_FILES = unctrl.def lock.def ffs.def
>  CHAPTERS = misc.tex
> diff --git a/newlib/libc/misc/Makefile.in b/newlib/libc/misc/Makefile.in
> index 0ada8de34e7a3a6084dbab4bfa7caf8cb7f8d8f3..e7925231c203897d917f41accf6560e3336895bc 100644
> --- a/newlib/libc/misc/Makefile.in
> +++ b/newlib/libc/misc/Makefile.in
> @@ -53,6 +53,9 @@ PRE_UNINSTALL = :
>  POST_UNINSTALL = :
>  build_triplet = @build@
>  host_triplet = @host@
> +@NEWLIB_RETARGETABLE_LOCKING_TRUE@am__append_1 = \
> +@NEWLIB_RETARGETABLE_LOCKING_TRUE@	lock.c
> +
>  DIST_COMMON = $(srcdir)/../../Makefile.shared $(srcdir)/Makefile.in \
>  	$(srcdir)/Makefile.am
>  subdir = misc
> @@ -72,14 +75,19 @@ LIBRARIES = $(noinst_LIBRARIES)
>  ARFLAGS = cru
>  lib_a_AR = $(AR) $(ARFLAGS)
>  lib_a_LIBADD =
> -am__objects_1 = lib_a-__dprintf.$(OBJEXT) lib_a-unctrl.$(OBJEXT) \
> -	lib_a-ffs.$(OBJEXT) lib_a-init.$(OBJEXT) lib_a-fini.$(OBJEXT)
> -@USE_LIBTOOL_FALSE@am_lib_a_OBJECTS = $(am__objects_1)
> +@NEWLIB_RETARGETABLE_LOCKING_TRUE@am__objects_1 =  \
> +@NEWLIB_RETARGETABLE_LOCKING_TRUE@	lib_a-lock.$(OBJEXT)
> +am__objects_2 = lib_a-__dprintf.$(OBJEXT) lib_a-unctrl.$(OBJEXT) \
> +	lib_a-ffs.$(OBJEXT) lib_a-init.$(OBJEXT) lib_a-fini.$(OBJEXT) \
> +	$(am__objects_1)
> +@USE_LIBTOOL_FALSE@am_lib_a_OBJECTS = $(am__objects_2)
>  lib_a_OBJECTS = $(am_lib_a_OBJECTS)
>  LTLIBRARIES = $(noinst_LTLIBRARIES)
>  libmisc_la_LIBADD =
> -am__objects_2 = __dprintf.lo unctrl.lo ffs.lo init.lo fini.lo
> -@USE_LIBTOOL_TRUE@am_libmisc_la_OBJECTS = $(am__objects_2)
> +@NEWLIB_RETARGETABLE_LOCKING_TRUE@am__objects_3 = lock.lo
> +am__objects_4 = __dprintf.lo unctrl.lo ffs.lo init.lo fini.lo \
> +	$(am__objects_3)
> +@USE_LIBTOOL_TRUE@am_libmisc_la_OBJECTS = $(am__objects_4)
>  libmisc_la_OBJECTS = $(am_libmisc_la_OBJECTS)
>  libmisc_la_LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) \
>  	$(LIBTOOLFLAGS) --mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) \
> @@ -252,7 +260,7 @@ top_builddir = @top_builddir@
>  top_srcdir = @top_srcdir@
>  AUTOMAKE_OPTIONS = cygnus
>  INCLUDES = $(NEWLIB_CFLAGS) $(CROSS_CFLAGS) $(TARGET_CFLAGS)
> -LIB_SOURCES = __dprintf.c unctrl.c ffs.c init.c fini.c
> +LIB_SOURCES = __dprintf.c unctrl.c ffs.c init.c fini.c $(am__append_1)
>  libmisc_la_LDFLAGS = -Xcompiler -nostdlib
>  @USE_LIBTOOL_TRUE@noinst_LTLIBRARIES = libmisc.la
>  @USE_LIBTOOL_TRUE@libmisc_la_SOURCES = $(LIB_SOURCES)
> @@ -271,7 +279,7 @@ DOCBOOK_CHEW = ${top_srcdir}/../doc/makedocbook.py
>  DOCBOOK_OUT_FILES = $(CHEWOUT_FILES:.def=.xml)
>  DOCBOOK_CHAPTERS = $(CHAPTERS:.tex=.xml)
>  CLEANFILES = $(CHEWOUT_FILES) $(CHEWOUT_FILES:.def=.ref) $(DOCBOOK_OUT_FILES)
> -CHEWOUT_FILES = unctrl.def ffs.def
> +CHEWOUT_FILES = unctrl.def lock.def ffs.def
>  CHAPTERS = misc.tex
>  all: all-am
>  
> @@ -372,6 +380,12 @@ lib_a-fini.o: fini.c
>  lib_a-fini.obj: fini.c
>  	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-fini.obj `if test -f 'fini.c'; then $(CYGPATH_W) 'fini.c'; else $(CYGPATH_W) '$(srcdir)/fini.c'; fi`
>  
> +lib_a-lock.o: lock.c
> +	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-lock.o `test -f 'lock.c' || echo '$(srcdir)/'`lock.c
> +
> +lib_a-lock.obj: lock.c
> +	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-lock.obj `if test -f 'lock.c'; then $(CYGPATH_W) 'lock.c'; else $(CYGPATH_W) '$(srcdir)/lock.c'; fi`
> +
>  mostlyclean-libtool:
>  	-rm -f *.lo
>  
> diff --git a/newlib/libc/misc/lock.c b/newlib/libc/misc/lock.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..1c69575b33f666c8170c2fe8473ad428f2741137
> --- /dev/null
> +++ b/newlib/libc/misc/lock.c
> @@ -0,0 +1,149 @@
> +/*
> +FUNCTION
> +<<__retarget_lock_init>>, <<__retarget_lock_init_recursive>>, <<__retarget_lock_close>>, <<__retarget_lock_close_recursive>>, <<__retarget_lock_acquire>>, <<__retarget_lock_acquire_recursive>>, <<__retarget_lock_try_acquire>>, <<__retarget_lock_try_acquire_recursive>>, <<__retarget_lock_release>>, <<__retarget_lock_release_recursive>>---locking routines
> +
> +INDEX
> +	_lock___sinit_lock
> +INDEX
> +	_lock___sfp_lock
> +INDEX
> +	_lock___atexit_lock
> +INDEX
> +	_lock___atexit_mutex
> +INDEX
> +	_lock___malloc_lock_object
> +INDEX
> +	_lock___env_lock_object
> +INDEX
> +	_lock___tz_lock_object
> +INDEX
> +	_lock___dd_hash_lock
> +
> +INDEX
> +	__retarget_lock_init
> +INDEX
> +	__retarget_lock_init_recursive
> +INDEX
> +	__retarget_lock_close
> +INDEX
> +	__retarget_lock_close_recursive
> +INDEX
> +	__retarget_lock_acquire
> +INDEX
> +	__retarget_lock_acquire_recursive
> +INDEX
> +	__retarget_lock_try_acquire
> +INDEX
> +	__retarget_lock_try_acquire_recursive
> +INDEX
> +	__retarget_lock_release
> +INDEX
> +	__retarget_lock_release_recursive
> +
> +ANSI_SYNOPSIS
> +	#include <lock.h>
> +	struct _lock _lock___sinit_lock;
> +	struct _lock _lock___sfp_lock;
> +	struct _lock _lock___atexit_lock;
> +	struct _lock _lock___atexit_mutex;
> +	struct _lock _lock___malloc_lock_object;
> +	struct _lock _lock___env_lock_object;
> +	struct _lock _lock___tz_lock_object;
> +	struct _lock _lock___dd_hash_lock;
> +
> +	void __retarget_lock_init (_LOCK_T * <[lock_ptr]>);
> +	void __retarget_lock_init_recursive (_LOCK_T * <[lock_ptr]>);
> +	void __retarget_lock_close (_LOCK_T <[lock]>);
> +	void __retarget_lock_close_recursive (_LOCK_T <[lock]>);
> +	void __retarget_lock_acquire (_LOCK_T <[lock]>);
> +	void __retarget_lock_acquire_recursive (_LOCK_T <[lock]>);
> +	int __retarget_lock_try_acquire (_LOCK_T <[lock]>);
> +	int __retarget_lock_try_acquire_recursive (_LOCK_T <[lock]>);
> +	void __retarget_lock_release (_LOCK_T <[lock]>);
> +	void __retarget_lock_release_recursive (_LOCK_T <[lock]>);
> +
> +DESCRIPTION
> +Newlib was configured to allow the target platform to provide the locking
> +routines and static locks at link time.  As such, a dummy default
> +implementation of these routines and static locks is provided for
> +single-threaded application to link successfully out of the box on bare-metal
> +systems.
> +
> +For multi-threaded applications the target platform is required to provide
> +an implementation for @strong{all} these routines and static locks.  If some
> +routines or static locks are missing, the link will fail with doubly defined
> +symbols.
> +
> +PORTABILITY
> +These locking routines and static lock are newlib-specific.  Supporting OS
> +subroutines are required for linking multi-threaded applications.
> +*/
> +
> +/* dummy lock routines and static locks for single-threaded apps */
> +
> +#include <sys/lock.h>
> +
> +struct _lock {
> +  char unused;
> +};
> +
> +struct _lock _lock___sinit_lock;
> +struct _lock _lock___sfp_lock;
> +struct _lock _lock___atexit_lock;
> +struct _lock _lock___atexit_mutex;
> +struct _lock _lock___malloc_lock_object;
> +struct _lock _lock___env_lock_object;
> +struct _lock _lock___tz_lock_object;
> +struct _lock _lock___dd_hash_lock;
> +
> +void
> +__retarget_lock_init (_LOCK_T *lock)
> +{
> +}
> +
> +void
> +__retarget_lock_init_recursive(_LOCK_T *lock)
> +{
> +}
> +
> +void
> +__retarget_lock_close(_LOCK_T lock)
> +{
> +}
> +
> +void
> +__retarget_lock_close_recursive(_LOCK_T lock)
> +{
> +}
> +
> +void
> +__retarget_lock_acquire (_LOCK_T lock)
> +{
> +}
> +
> +void
> +__retarget_lock_acquire_recursive (_LOCK_T lock)
> +{
> +}
> +
> +int
> +__retarget_lock_try_acquire(_LOCK_T lock)
> +{
> +  return 1;
> +}
> +
> +int
> +__retarget_lock_try_acquire_recursive(_LOCK_T lock)
> +{
> +  return 1;
> +}
> +
> +void
> +__retarget_lock_release (_LOCK_T lock)
> +{
> +}
> +
> +void
> +__retarget_lock_release_recursive (_LOCK_T lock)
> +{
> +}
> diff --git a/newlib/libc/misc/misc.tex b/newlib/libc/misc/misc.tex
> index 22c313eb15c7676443ff4c928c8c76cc038f3f0f..6afd1be5c4a1e90ffd64881c63c5132e144ad364 100644
> --- a/newlib/libc/misc/misc.tex
> +++ b/newlib/libc/misc/misc.tex
> @@ -4,6 +4,7 @@ This chapter describes miscellaneous routines not covered elsewhere.
>  
>  @menu 
>  * ffs::      Return first bit set in a word
> +* lock::     Retargetable locking routines
>  * unctrl::   Return printable representation of a character
>  @end menu
>  
> @@ -11,4 +12,7 @@ This chapter describes miscellaneous routines not covered elsewhere.
>  @include misc/ffs.def
>  
>  @page
> +@include misc/lock.def
> +
> +@page
>  @include misc/unctrl.def
> diff --git a/newlib/newlib.hin b/newlib/newlib.hin
> index d03dfac0eea6a8917a92b8f0f3584c2cd42b9388..397bc9b96eafddace3a75be509157040654b6fde 100644
> --- a/newlib/newlib.hin
> +++ b/newlib/newlib.hin
> @@ -82,6 +82,9 @@
>  /* Define if small footprint nano-formatted-IO implementation used.  */
>  #undef _NANO_FORMATTED_IO
>  
> +/* Define if using retargetable functions for default lock routines.  */
> +#undef _RETARGETABLE_LOCKING
> +
>  /*
>   * Iconv encodings enabled ("to" direction)
>   */


-- 
Corinna Vinschen
Cygwin Maintainer
Red Hat