Changeset e81ef51 in rtems


Ignore:
Timestamp:
02/17/98 14:12:01 (25 years ago)
Author:
Joel Sherrill <joel.sherrill@…>
Branches:
4.10, 4.11, 4.8, 4.9, 5, master
Children:
9646d5be
Parents:
aa8a8c72
Message:

Patch from Ralf Corsepius <corsepiu@…>:

Yep, I have a bunch of bug-fixes and additions pending (Yet another monster
patch, ... I can hear you scream :-).

1) configure.in : one AC_CONFIG_HEADER(...) line too much.

2) configure.in: gcc28 support is enabled by default, i.e. if no
--enable-gcc28 option is passed on the command line. I am not sure if this
is intentional.

IMO, AC_ARG_ENABLE for --enable-gcc28 should look like:

AC_ARG_ENABLE(gcc28, \
[ --enable-gcc28 enable use of gcc 2.8.x features], \
[case "${enableval}" in

yes) RTEMS_USE_GCC272=no ;;
no) RTEMS_USE_GCC272=yes ;;
*) AC_MSG_ERROR(bad value ${enableval} for gcc-28 option) ;;

esac],[RTEMS_USE_GCC272=yes])

3) At the end of c/src/exec/score/cpu/m68k/m68k.h

#ifdef cplusplus
}
#endif

#endif /* !ASM */

in my opinion these two statements should be swapped:

#endif /* !ASM */

#ifdef cplusplus
}
#endif

I didn't try to compile for m68k, but does't this give an error? Is it
compensated somewhere else - or didn't I look carefully enough?

5) configure.in: --enable-cpp should probably be renamed to --enable-cxx, as
gnu-programs use "cxx" to specify C++ specific configure options, while cpp
is used for the preprocessor (e.g egcs uses --with-cxx-includedir, autoconf
internally uses $CXX),

6) The macro files from aclocal/*.m4 contain the buggy sed-rules formerly
contained in aclocal..m4, i.e. the sed/sort-bug fix to aclocal.m4 didn't
make it to aclocal/*.m4. I think I should feel guilty for that - Obviously I
submitted the contents of an old aclocal-directory last time. - Sorry.

7) For sh-rtems, we currently need to add additional managers to
MANAGERS_REQUIRED (from inside of custom/*.cfg). Currently MANAGERS_REQUIRED
is defined in make/compilers/*.cfg. This seems to prevent overriding
MANAGERS_REQUIRED from custom/*.cfg files - Obviously the files are included
in such a way that the settings from compilers/*cfg always override settings
from custom/*.cfg files.

Furthermore, I think, defining MANAGERS_* inside gcc-<target>.cfg files is
not correct - MANAGERS are not gcc-variant-dependent, but depend
on targets/bsps and therefore should be defined in a bsp/target dependent
file, e.g. in custom/*.cfg or target.cfg.in.

I think defining default settings for MANAGERS* in custom/default.cfg could
be an appropriate location. But this requires all custom/*.cfg files to
include default.cfg, which *-posix.cfg files don't seem to do.

Therefore I would like propose to move MANAGERS* to target.cfg.in - they are
included by all custom/*.cfg files. Perhaps we/you should use this
opportunity to merge parts from custom/default.cfg into target.cfg.in. This
ensures to have the setting included once per target makefile and will open
the opportunity to have autoconf doing additional work on
bsp-configurations.

Peanuts sofar, ... but here it comes ... (:-)

8) I am preparing a major enhancement to autoconf support for
gnutools/compilers. It is not yet finished, but usable and I'll therefore
attach a preliminary version to this mail.

Motivation:

  • Fix problems with --enable-gcc28, if target-cc is not gcc28 compatible
  • Fix -pipe problems
  • Fix problems with hard-coded paths in configuration files (esp. posix)
  • Fix consistency problems with explictly given gnutools and gcc's gnutools

Currently included:

  • detection and checking of host and target compiler (gcc/g++)
  • checking if target gnutools are in path
  • checking if <target>-gcc -specs works (autodisabling gcc28 if not)
  • checking if <target>-gcc -pipe works

Todo :

  • *posix.cfg files are not yet adapted => The hard-coded paths for these systems are still in use.
  • Check if the host compiler $CC is properly propagated to the Makefiles (I doubt it, but this should not matter)
  • Check if rtems' generic tools still work properly (It looks like, but who knows)
  • Integrate CXX support into default.cfg or gcc-target-default.cfg (It looks like C++ support is only used by posix BSPs)
  • Automatically handle RANLIB/MKLIB for targets
  • Plenty ... (:-)

Open problems:

  • Untested for non-gcc compatible host and target compilers. This should be no problem if the tools are named follow gnutool's naming convention and are included in $PATH while running configure.
  • Intentionally using different tools than that gcc has been configured for, e.g. use a different assembler ? This should be still possible if XX_FOR_TARGET is hard-coded into custom/*.cfg. I don't see why anybody should want to do this, but who knows?

I have tested this version on linux and solaris hosts, with gcc's
directories mounted at weird non-standard mount points, using egcs
(linux/sh-rtemscoff), gcc-2.7.2.2 using native tools (solaris), gcc-2.7.2.3
w/ gnutools (solaris/linux). I don't expect it to break anything, but of
cause I can't promise it. It will break most/all *-posix.cfg configuration
almost for certain, but not more as rtems' current *posix.cfg configurations
already do (hard-coded configurations).

I am not sure if this is ready to be included into the next snapshot or not.
Perhaps you might try this on your systems and if it you don't notice
serious bugs you might put it into the snapshot for public testing (I don't
like this, but I don't see another possiblity to test generality).

I enclose a patch for configure.in and some configuration files which
comprizes fixes for all items mentioned except of #3 . Don't forget to run
"aclocal -I aclocal; autoconf;" after applying the patch (:-).

Files:
5 edited

Legend:

Unmodified
Added
Removed

  • README.configure

    raa8a8c72 re81ef51  
    2424        --disable-tests
    2525        --disable-ka9q
    26         --enable-cpp
     26        --enable-cxx
    2727        --enable-gcc28               (also use enable-libcdir when disabled)
    2828        --enable-gmake-print-directory
    … …  
    4343
    4444By default, the RTEMS support of C++ is disabled.  It can be enabled
    45 with the --enable-cpp option. If the rtems++ C++ library is installed
     45with the --enable-cxx option. If the rtems++ C++ library is installed
    4646it will also be build.
    4747

  • aclocal.m4

    raa8a8c72 re81ef51  
    1 dnl some macros for rtems host configuration checks
    2 dnl
    3 dnl Author: Ralf Corsepius (corsepiu@faw.uni-ulm.de), 97/11/29
    4 dnl
    5 dnl Last Modified: 98/01/10
    6 dnl
    7 dnl  $Id$
    8 dnl
     1dnl aclocal.m4 generated automatically by aclocal 1.2
     2
     3dnl $Id$
    94
    105dnl macro to detect mkdir
    … …  
    4540])
    4641
     42
     43dnl $Id$
     44
     45dnl canonicalize target name
     46dnl NOTE: Most rtems targets do not fullfil autoconf's
     47dnl target naming conventions "processor-vendor-os"
     48dnl Therefore autoconf's AC_CANONICAL_TARGET will fail for them
     49dnl and we have to fix it for rtems ourselves
     50
     51AC_DEFUN(RTEMS_CANONICAL_TARGET_CPU,
     52[AC_MSG_CHECKING(rtems target cpu)
     53changequote(<<, >>)dnl
     54target_cpu=`echo $target | sed 's%^\([^-]*\)-\(.*\)$%\1%'`
     55changequote([, ])dnl
     56AC_MSG_RESULT($target_cpu)
     57])
     58
     59dnl
     60dnl $Id$
     61dnl
     62dnl Check for target gcc
     63dnl
     64dnl Adaptation of autoconf-2.12's AC_PROG_CC to rtems
     65dnl
     66dnl 98/02/10 Ralf Corsepius     (corsepiu@faw.uni-ulm.de)
     67dnl
     68
     69AC_DEFUN(RTEMS_PROG_CC,
     70[
     71AC_BEFORE([$0], [AC_PROG_CPP])dnl
     72AC_BEFORE([$0], [AC_PROG_CC])dnl
     73AC_CHECK_PROG(CC, gcc, gcc)
     74if test -z "$CC"; then
     75  AC_CHECK_PROG(CC, cc, cc, , , /usr/ucb/cc)
     76  test -z "$CC" && AC_MSG_ERROR([no acceptable cc found in \$PATH])
     77fi
     78
     79RTEMS_PROG_CC_WORKS
     80AC_PROG_CC_GNU
     81
     82if test $ac_cv_prog_gcc = yes; then
     83  GCC=yes
     84dnl Check whether -g works, even if CFLAGS is set, in case the package
     85dnl plays around with CFLAGS (such as to build both debugging and
     86dnl normal versions of a library), tasteless as that idea is.
     87  ac_test_CFLAGS="${CFLAGS+set}"
     88  ac_save_CFLAGS="$CFLAGS"
     89  CFLAGS=
     90  AC_PROG_CC_G
     91  if test "$ac_test_CFLAGS" = set; then
     92    CFLAGS="$ac_save_CFLAGS"
     93  elif test $ac_cv_prog_cc_g = yes; then
     94    CFLAGS="-g -O2"
     95  else
     96    CFLAGS="-O2"
     97  fi
     98else
     99  GCC=
     100  test "${CFLAGS+set}" = set || CFLAGS="-g"
     101fi
     102
     103CC_FOR_TARGET=$CC
     104rtems_cv_prog_gcc=$ac_cv_prog_gcc
     105rtems_cv_prog_cc_g=$ac_cv_prog_cc_g
     106
     107dnl restore initial values
     108unset CC
     109unset ac_cv_prog_gcc
     110unset ac_cv_prog_cc_g
     111unset ac_cv_prog_CC
     112])
     113
     114
     115dnl Almost identical to AC_PROG_CC_WORKS
     116dnl added malloc to program fragment, because rtems has its own malloc
     117dnl which is not available while bootstrapping rtems
     118
     119AC_DEFUN(RTEMS_PROG_CC_WORKS,
     120[AC_MSG_CHECKING([whether the target C compiler ($CC $CFLAGS $LDFLAGS) works])
     121AC_LANG_SAVE
     122AC_LANG_C
     123AC_TRY_COMPILER(
     124[void *malloc() { return 0; }
     125 main(){return(0);}],
     126rtems_cv_prog_cc_works, rtems_cv_prog_cc_cross)
     127AC_LANG_RESTORE
     128AC_MSG_RESULT($rtems_cv_prog_cc_works)
     129if test $rtems_cv_prog_cc_works = no; then
     130  AC_MSG_ERROR([installation or configuration problem: target C compiler cannot create executables.])
     131fi
     132AC_MSG_CHECKING([whether the target C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler])
     133AC_MSG_RESULT($rtems_cv_prog_cc_cross)
     134])
     135
     136dnl
     137dnl $Id$
     138dnl
     139dnl Check whether the target compiler accepts -specs
     140dnl
     141dnl 98/02/11 Ralf Corsepius     corsepiu@faw.uni-ulm.de
     142dnl
     143
     144AC_DEFUN(RTEMS_GCC_SPECS,
     145[AC_REQUIRE([RTEMS_PROG_CC])
     146AC_CACHE_CHECK(whether $CC_FOR_TARGET accepts -specs,rtems_cv_gcc_specs,
     147[touch confspec
     148echo 'void f(){}' >conftest.c
     149if test -z "`${CC_FOR_TARGET} -specs confspec -c conftest.c 2>&1`";then
     150  rtems_cv_gcc_specs=yes
     151else
     152  rtems_cv_gcc_specs=no
     153fi
     154rm -f confspec conftest*
     155])])
     156
     157dnl
     158dnl $Id$
     159dnl
     160dnl Check whether the target compiler accepts -pipe
     161dnl
     162dnl 98/02/11 Ralf Corsepius     corsepiu@faw.uni-ulm.de
     163dnl
     164
     165AC_DEFUN(RTEMS_GCC_PIPE,
     166[AC_REQUIRE([RTEMS_PROG_CC])
     167AC_CACHE_CHECK(whether $CC_FOR_TARGET accepts --pipe,rtems_cv_gcc_pipe,
     168[
     169echo 'void f(){}' >conftest.c
     170if test -z "`${CC_FOR_TARGET} --pipe -c conftest.c 2>&1`";then
     171  rtems_cv_gcc_pipe=yes
     172else
     173  rtems_cv_gcc_pipe=no
     174fi
     175rm -f conftest*
     176])])
     177
     178dnl
     179dnl $Id$
     180dnl
     181dnl Check for target g++
     182dnl
     183dnl Adaptation of autoconf-2.12's AC_PROG_CXX to rtems
     184dnl
     185dnl 98/02/10 Ralf Corsepius (corsepiu@faw.uni-ulm.de)
     186dnl
     187 
     188AC_DEFUN(RTEMS_PROG_CXX,
     189[
     190AC_BEFORE([$0], [AC_PROG_CXXCPP])dnl
     191AC_BEFORE([$0], [AC_PROG_CXX])dnl
     192AC_CHECK_PROGS(CXX, $CCC c++ g++ gcc CC cxx cc++, gcc)
     193
     194RTEMS_PROG_CXX_WORKS
     195AC_PROG_CXX_GNU
     196
     197if test $ac_cv_prog_gxx = yes; then
     198  GXX=yes
     199dnl Check whether -g works, even if CXXFLAGS is set, in case the package
     200dnl plays around with CXXFLAGS (such as to build both debugging and
     201dnl normal versions of a library), tasteless as that idea is.
     202  ac_test_CXXFLAGS="${CXXFLAGS+set}"
     203  ac_save_CXXFLAGS="$CXXFLAGS"
     204  CXXFLAGS=
     205  AC_PROG_CXX_G
     206  if test "$ac_test_CXXFLAGS" = set; then
     207    CXXFLAGS="$ac_save_CXXFLAGS"
     208  elif test $ac_cv_prog_cxx_g = yes; then
     209    CXXFLAGS="-g -O2"
     210  else
     211    CXXFLAGS="-O2"
     212  fi
     213else
     214  GXX=
     215  test "${CXXFLAGS+set}" = set || CXXFLAGS="-g"
     216fi
     217CXX_FOR_TARGET=$CXX
     218
     219dnl restore initial values
     220unset CXX
     221unset ac_cv_prog_gxx
     222])
     223
     224
     225dnl Almost identical to AC_PROG_CXX_WORKS
     226dnl Additional handling of malloc
     227dnl NOTE: using newlib with a native compiler is cross-compiling, indeed.
     228AC_DEFUN(RTEMS_PROG_CXX_WORKS,
     229[AC_MSG_CHECKING([whether the target C++ compiler ($CXX $CXXFLAGS $LDFLAGS) works])
     230AC_LANG_SAVE
     231AC_LANG_CPLUSPLUS
     232
     233dnl this fails if rtems uses newlib, because rtems has its own malloc which
     234dnl is not available at bootstrap
     235AC_TRY_COMPILER(
     236  [main(){return(0);}],
     237  rtems_cv_prog_cxx_works, rtems_cv_prog_cxx_cross)
     238if test "$rtems_cv_prog_cxx_works" = "no"; then
     239  dnl now retry with our own version of malloc
     240  AC_TRY_COMPILER(
     241    [extern "C" void *malloc();
     242     void *malloc() { return (0); }
     243     main(){return(0);}],
     244    rtems_cv_prog_cxx_works, rtems_cv_prog_cxx_cross)
     245fi
     246AC_LANG_RESTORE
     247AC_MSG_RESULT($rtems_cv_prog_cxx_works)
     248if test $rtems_cv_prog_cxx_works = no; then
     249  AC_MSG_ERROR([installation or configuration problem: target C++ compiler cannot create executables.])
     250fi
     251AC_MSG_CHECKING([whether the target C++ compiler ($CXX $CXXFLAGS $LDFLAGS) is a cross-compiler])
     252AC_MSG_RESULT($rtems_cv_prog_cxx_cross)
     253])
     254
     255dnl $Id$
     256dnl
     257dnl Set target tools
     258dnl
     259dnl 98/02/12 Ralf Corsepius     (corsepiu@faw.uni-ulm.de)
     260dnl
     261
     262AC_DEFUN(RTEMS_CANONICALIZE_TOOLS,
     263[AC_REQUIRE([RTEMS_PROG_CC])dnl
     264if test "$rtems_cv_prog_gcc" = "yes" ; then
     265  dnl We are using gcc, now ask it about its tools
     266  dnl Necessary if gcc was configured to use the target's native tools
     267  dnl or uses prefixes for gnutools (e.g. gas instead of as)
     268  AR_FOR_TARGET=`$CC_FOR_TARGET --print-prog-name=ar`
     269  AS_FOR_TARGET=`$CC_FOR_TARGET --print-prog-name=as`
     270  LD_FOR_TARGET=`$CC_FOR_TARGET --print-prog-name=ld`
     271  NM_FOR_TARGET=`$CC_FOR_TARGET --print-prog-name=nm`
     272  RANLIB_FOR_TARGET=`$CC_FOR_TARGET --print-prog-name=ranlib`
     273fi
     274
     275dnl check whether the tools exist
     276dnl FIXME: What shall be done if they don't exist?
     277
     278dnl NOTE: CC_FOR_TARGET should always be valid at this point,
     279dnl       cf. RTEMS_PROG_CC 
     280AC_PATH_PROG(CC_FOR_TARGET,"$program_prefix"gcc,no)
     281
     282dnl FIXME: This may fail if the compiler has not been recognized as gcc
     283dnl       and uses tools with different names
     284AC_PATH_PROG(AR_FOR_TARGET,"$program_prefix"ar,no)
     285AC_PATH_PROG(AS_FOR_TARGET,"$program_prefix"as,no)
     286AC_PATH_PROG(NM_FOR_TARGET,"$program_prefix"nm,no)
     287AC_PATH_PROG(LD_FOR_TARGET,"$program_prefix"ld,no)
     288
     289dnl NOTE: This is doubtful, but should not disturb all current rtems'
     290dnl       targets (remark: solaris fakes ranlib!!)
     291AC_PATH_PROG(RANLIB_FOR_TARGET,"$program_prefix"ranlib,no)
     292
     293dnl NOTE: These may not be available, if not using gnutools
     294AC_PATH_PROG(OBJCOPY_FOR_TARGET,"$program_prefix"objcopy,no)
     295AC_PATH_PROG(SIZE_FOR_TARGET,"$program_prefix"size,no)
     296])
     297
     298dnl $Id$
     299
     300dnl RTEMS_CHECK_MAKEFILE(path)
     301dnl Search for Makefile.in's within the directory starting
     302dnl at path and append an entry for Makefile to global variable
     303dnl "makefiles" (from configure.in) for each Makefile.in found
     304dnl
     305AC_DEFUN(RTEMS_CHECK_MAKEFILE,
     306[RTEMS_CHECK_FILES_IN($1,Makefile,makefiles)
     307])
     308
     309dnl $Id$
     310
    47311dnl RTEMS_CHECK_FILES_IN(path,file,var)
    48312dnl path .. path relative to srcdir, where to start searching for files
    49313dnl file .. name of the files to search for
    50 dnl var  .. shell variable to append found files
     314dnl var  .. shell variable to append files found
    51315AC_DEFUN(RTEMS_CHECK_FILES_IN,
    52316[
    … …  
    64328])
    65329
    66 dnl RTEMS_CHECK_MAKEFILE(path)
    67 dnl Search for Makefile.in's within the directory starting
    68 dnl at path and append an entry for Makefile to global variable
    69 dnl "makefiles" (from configure.in) for each Makefile.in found
    70 dnl
    71 AC_DEFUN(RTEMS_CHECK_MAKEFILE,
    72 [RTEMS_CHECK_FILES_IN($1,Makefile,makefiles)
    73 ])
    74 
    75 dnl canonicalize target name
    76 dnl NOTE: Most rtems targets do not fullfil autoconf's
    77 dnl target naming conventions "processor-vendor-os"
    78 dnl Therefore autoconf's AC_CANONICAL_TARGET will fail for them
    79 dnl and we have to fix it for rtems ourselves
    80 
    81 AC_DEFUN(RTEMS_CANONICAL_TARGET_CPU,
    82 [AC_MSG_CHECKING(rtems target cpu)
    83 changequote(<<, >>)dnl
    84 target_cpu=`echo $target | sed 's%^\([^-]*\)-\(.*\)$%\1%'`
    85 changequote([, ])dnl
    86 AC_MSG_RESULT($target_cpu)
    87 ])
     330

  • c/src/make/compilers/gcc-target-default.cfg

    raa8a8c72 re81ef51  
    159159# NOTE: we override COMPILE.c
    160160#
    161 # NOTE: Remove -pipe if it causes you problems.  Using it can decrease
    162 #       compile time.
    163 #
    164161
    165162COMPILE.c=$(CC) $(CFLAGS) $(XCFLAGS) -c
    166163
    167164${ARCH}/%.o: %.c
    168         ${COMPILE.c} -pipe -o $@ $<
     165        ${COMPILE.c} -o $@ $<
    169166
    170167${ARCH}/%.o: %.cc
    171         ${COMPILE.c} -pipe -o $@ $<
     168        ${COMPILE.c} -o $@ $<
    172169
    173170${ARCH}/%.o: %.S
    174         ${COMPILE.c} -pipe -DASM -o $@ $<
     171        ${COMPILE.c} -DASM -o $@ $<
    175172
    176173# strip out C++ style comments.
    … …  
    225222endif
    226223
    227 
    228 # List (possibly empty) of required managers
    229 # We require:
    230 #    region  -- used by lib/libcsupport for malloc()
    231 #    ext     -- used by libc for libc reentrancy hooks
    232 
    233 MANAGERS_REQUIRED=region ext sem
    234 
    235 # Create a RTEMS executable based on MANAGERS which was set in
    236 #  app's Makefile
    237 
    238 MANAGERS_NOT_WANTED=$(filter-out $(MANAGERS), $(MANAGER_LIST))
    239 MANAGERS_NOT_WANTED:=$(filter-out $(MANAGERS_REQUIRED), $(MANAGERS_NOT_WANTED))
    240 
    241224# spell out all the LINK_FILE's, rather than using -lbsp, so
    242225#  that $(LINK_FILES) can be a dependency

  • make/compilers/gcc-portsw.cfg

    raa8a8c72 re81ef51  
    229229endif
    230230
    231 # List (possibly empty) of required managers
    232 # We require:
    233 #    region  -- used by lib/libcsupport for malloc()
    234 #    ext     -- used by libc for libc reentrancy hooks
    235 
    236 MANAGERS_REQUIRED=region ext sem
    237 
    238 # Create a RTEMS executable based on MANAGERS which was set in
    239 #  app's Makefile
    240 
    241 MANAGERS_NOT_WANTED=$(filter-out $(MANAGERS), $(MANAGER_LIST))
    242 MANAGERS_NOT_WANTED:=$(filter-out $(MANAGERS_REQUIRED), $(MANAGERS_NOT_WANTED))
    243231
    244232# spell out all the LINK_FILE's, rather than using -lbsp, so

  • make/compilers/gcc-target-default.cfg

    raa8a8c72 re81ef51  
    159159# NOTE: we override COMPILE.c
    160160#
    161 # NOTE: Remove -pipe if it causes you problems.  Using it can decrease
    162 #       compile time.
    163 #
    164161
    165162COMPILE.c=$(CC) $(CFLAGS) $(XCFLAGS) -c
    166163
    167164${ARCH}/%.o: %.c
    168         ${COMPILE.c} -pipe -o $@ $<
     165        ${COMPILE.c} -o $@ $<
    169166
    170167${ARCH}/%.o: %.cc
    171         ${COMPILE.c} -pipe -o $@ $<
     168        ${COMPILE.c} -o $@ $<
    172169
    173170${ARCH}/%.o: %.S
    174         ${COMPILE.c} -pipe -DASM -o $@ $<
     171        ${COMPILE.c} -DASM -o $@ $<
    175172
    176173# strip out C++ style comments.
    … …  
    225222endif
    226223
    227 
    228 # List (possibly empty) of required managers
    229 # We require:
    230 #    region  -- used by lib/libcsupport for malloc()
    231 #    ext     -- used by libc for libc reentrancy hooks
    232 
    233 MANAGERS_REQUIRED=region ext sem
    234 
    235 # Create a RTEMS executable based on MANAGERS which was set in
    236 #  app's Makefile
    237 
    238 MANAGERS_NOT_WANTED=$(filter-out $(MANAGERS), $(MANAGER_LIST))
    239 MANAGERS_NOT_WANTED:=$(filter-out $(MANAGERS_REQUIRED), $(MANAGERS_NOT_WANTED))
    240 
    241224# spell out all the LINK_FILE's, rather than using -lbsp, so
    242225#  that $(LINK_FILES) can be a dependency
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