| Message ID | 504641B2.6040003@gjlay.de |
|---|---|
| State | New |
| Headers | show |
> -----Original Message----- > From: Georg-Johann Lay [] > Sent: Tuesday, September 04, 2012 12:00 PM > To: Weddington, Eric > Cc: Gabriel Dos Reis; Richard Guenther; gcc-patches@gcc.gnu.org; Denis > Chertykov; Joerg Wunsch > Subject: Re: [Patch,avr] PR54461: Better AVR-Libc integration > > So here is an updated version of the patch. > Instead of "with_avrlibc = yes" it does "with_avrlibc != no". > > Just like the first version, --with-avrlibc[=*] is only recognized > if avr-gcc is not configured for RTEMS, i.e. RTEMS users don't need > to set --with-avrlibc=no in order to get a complete libgcc. > Sorry, I'm a bit confused. With your new patch... - If I build GCC, for the avr target (plain), without specifying the --with-avr-libc=<> switch, does it default to "yes"? - If I build GCC, for the avr-rtems target, without specifying the --with-avr-libc=<> switch, does it default to "no"? Because the above is what I would expect the default behavior to be. Doing that would certainly help with backwards compatibility for those building toolchain distributions. I would think that the user has to specify the --with-avr-libc=<> flag to explicitly deviate from common usage and practice. Eric Weddington
On Tue, Sep 4, 2012 at 1:00 PM, Georg-Johann Lay <avr@gjlay.de> wrote: > Weddington, Eric wrote: >> >>>>> Can you explain this? A typical build of avr tools goes like >>>>> >>>>> 1) configure, build and install binutils >>>>> 2) configure, build and install the compiler >>>>> 3) configure, build and install AVR-Libc >>>>> >>>>> so that in step 2 no checking is possible because there is no -lc yet. >>>>> Or do you mean a check at run time (of the compiler)? >>>> 4) build and install the real compiler >>>> >>>> at which time you have AVR-libc available. AT least that's how you >>>> "bootstrap" a glibc cross. >>> avr-gcc has had a "simplified" build process for a while, as it almost never >>> needed to have a avr-gcc hosted on an avr platform. It is usually >>> built as a cross-compiler that always run on the build platform. >>> >>> What I was suggesting earlier is that we shouldn't continue patching >>> the AVR target as if the current state is almost ideal. Pick a libc -- avr- >>> libc >>> appears to be the natural implementation -- and make it the default as >>> opposed to adding nobs. >> >> I also strongly agree with this. >> >> AFAIK, the only project that uses newlib as the C library for the AVR target >> is RTEMS, because, AIUI, they need to have the POSIX interface. The vast >> majority of AVR users have a toolchain that uses avr-libc. > > So here is an updated version of the patch. > Instead of "with_avrlibc = yes" it does "with_avrlibc != no". > > Just like the first version, --with-avrlibc[=*] is only recognized > if avr-gcc is not configured for RTEMS, i.e. RTEMS users don't need > to set --with-avrlibc=no in order to get a complete libgcc. Thanks! I am satisfied with this. -- Gaby
Weddington, Eric wrote: > >> From: Georg-Johann Lay >> >> So here is an updated version of the patch. >> Instead of "with_avrlibc = yes" it does "with_avrlibc != no". >> >> Just like the first version, --with-avrlibc[=*] is only recognized >> if avr-gcc is not configured for RTEMS, i.e. RTEMS users don't need >> to set --with-avrlibc=no in order to get a complete libgcc. > > Sorry, I'm a bit confused. With your new patch... > > - If I build GCC, for the avr target (plain), without specifying > the --with-avr-libc=<> switch, does it default to "yes"? Yes. Anything except an explicit "no" is treated like "yes". > - If I build GCC, for the avr-rtems target, without specifying > the --with-avr-libc=<> switch, does it default to "no"? Notice the switch is called --with-avrlibc. The option is ignored for avr-*-rtems*, thus is similar to "no", thus yes for the question. > Because the above is what I would expect the default behavior to be. > Doing that would certainly help with backwards compatibility for those > building toolchain distributions. > > I would think that the user has to specify the --with-avr-libc=<> flag > to explicitly deviate from common usage and practice. Yes, that's the case. Except for users that want avr-*-* without AVR-Libc and with newlib or some other libc flavor. Johann
> -----Original Message----- > From: Georg-Johann Lay [] > Sent: Tuesday, September 04, 2012 1:03 PM > To: Weddington, Eric > Cc: Gabriel Dos Reis; Richard Guenther; gcc-patches@gcc.gnu.org; Denis > Chertykov; Joerg Wunsch > Subject: Re: [Patch,avr] PR54461: Better AVR-Libc integration > > > I would think that the user has to specify the --with-avr-libc=<> flag > > to explicitly deviate from common usage and practice. > > Yes, that's the case. Except for users that want avr-*-* without > AVR-Libc and with newlib or some other libc flavor. Excellent! Thanks for the detailed explanation, and sorry for my confusion. I'm good with the patch, then. Eric
Index: configure =================================================================== --- configure (revision 190922) +++ configure (working copy) @@ -3499,6 +3499,13 @@ case "${target}" in arm-*-riscix*) noconfigdirs="$noconfigdirs ld target-libgloss" ;; + avr-*-rtems*) + ;; + avr-*-*) + if test x${with_avrlibc} != xno; then + noconfigdirs="$noconfigdirs target-newlib target-libgloss" + fi + ;; c4x-*-* | tic4x-*-*) noconfigdirs="$noconfigdirs target-libgloss" ;; Index: configure.ac =================================================================== --- configure.ac (revision 190922) +++ configure.ac (working copy) @@ -891,6 +891,13 @@ case "${target}" in arm-*-riscix*) noconfigdirs="$noconfigdirs ld target-libgloss" ;; + avr-*-rtems*) + ;; + avr-*-*) + if test x${with_avrlibc} != xno; then + noconfigdirs="$noconfigdirs target-newlib target-libgloss" + fi + ;; c4x-*-* | tic4x-*-*) noconfigdirs="$noconfigdirs target-libgloss" ;; Index: libgcc/config/avr/t-avrlibc =================================================================== --- libgcc/config/avr/t-avrlibc (revision 0) +++ libgcc/config/avr/t-avrlibc (revision 0) @@ -0,0 +1,66 @@ +# This file is used if not configured --with-avrlibc=no +# +# AVR-Libc comes with hand-optimized float routines. +# For historical reasons, these routines live in AVR-Libc +# and not in libgcc and use the same function names like libgcc. +# To get the best support, i.e. always use the routines from +# AVR-Libc, we remove these routines from libgcc. +# +# See also PR54461. +# +# +# Arithmetic: +# __addsf3 __subsf3 __divsf3 __mulsf3 __negsf2 +# +# Comparison: +# __cmpsf2 __unordsf2 +# __eqsf2 __lesf2 __ltsf2 __nesf2 __gesf2 __gtsf2 +# +# Conversion: +# __fixsfdi __fixunssfdi __floatdisf __floatundisf +# __fixsfsi __fixunssfsi __floatsisf __floatunsisf +# +# +# These functions are contained in modules: +# +# _addsub_sf.o: __addsf3 __subsf3 +# _mul_sf.o: __mulsf3 +# _div_sf.o: __divsf3 +# _negate_sf.o: __negsf2 +# +# _compare_sf.o: __cmpsf2 +# _unord_sf.o: __unordsf2 +# _eq_sf.o: __eqsf2 +# _ne_sf.o: __nesf2 +# _ge_sf.o: __gesf2 +# _gt_sf.o: __gtsf2 +# _le_sf.o: __lesf2 +# _lt_sf.o: __ltsf2 +# +# _fixsfdi.o: __fixsfdi +# _fixunssfdi.o: __fixunssfdi +# _fixunssfsi.o: __fixunssfsi +# _floatdisf.o: __floatdisf +# _floatundisf.o: __floatundisf +# _sf_to_si.o: __fixsfsi +# _si_to_sf.o: __floatsisf +# _usi_to_sf.o: __floatunsisf + + +# SFmode +LIB2FUNCS_EXCLUDE += \ + _addsub_sf \ + _negate_sf \ + _mul_sf _div_sf \ + \ + _compare_sf \ + _unord_sf \ + _eq_sf _ne_sf \ + _gt_sf _ge_sf \ + _lt_sf _le_sf \ + \ + _si_to_sf _sf_to_si \ + _usi_to_sf _sf_to_usi \ + _fixunssfsi _fixsfdi \ + _fixunssfdi \ + _floatdisf _floatundisf Index: libgcc/config.host =================================================================== --- libgcc/config.host (revision 190922) +++ libgcc/config.host (working copy) @@ -380,6 +380,9 @@ avr-*-rtems*) avr-*-*) # Make HImode functions for AVR tmake_file="${cpu_type}/t-avr t-fpbit" + if test x${with_avrlibc} != xno; then + tmake_file="$tmake_file ${cpu_type}/t-avrlibc" + fi tm_file="$tm_file avr/avr-lib.h" ;; bfin*-elf*) Index: gcc/config/avr/avr-c.c =================================================================== --- gcc/config/avr/avr-c.c (revision 190922) +++ gcc/config/avr/avr-c.c (working copy) @@ -148,6 +148,10 @@ avr_cpu_cpp_builtins (struct cpp_reader cpp_define_formatted (pfile, "__AVR_SFR_OFFSET__=0x%x", avr_current_arch->sfr_offset); +#ifdef WITH_AVRLIBC + cpp_define (pfile, "__WITH_AVRLIBC__"); +#endif /* WITH_AVRLIBC */ + /* Define builtin macros so that the user can easily query if or if not non-generic address spaces (and which) are supported. This is only supported for C. For C++, a language extension is needed Index: gcc/config/avr/avrlibc.h =================================================================== --- gcc/config/avr/avrlibc.h (revision 0) +++ gcc/config/avr/avrlibc.h (revision 0) @@ -0,0 +1,31 @@ +/* Definitions of target machine for the GNU compiler collection + for Atmel AVR micro controller if configured for AVR-Libc. + Copyright (C) 2012 + Free Software Foundation, Inc. + Contributed by Georg-Johann Lay (avr@gjlay.de) + +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. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +/* AVR-Libc implements functions from libgcc.a in libm.a, see PR54461. */ + +#undef LIBGCC_SPEC +#define LIBGCC_SPEC \ + "%{!mmcu=at90s1*:%{!mmcu=attiny11:%{!mmcu=attiny12:%{!mmcu=attiny15:%{!mmcu=attiny28: -lgcc -lm }}}}}" + +#undef LINK_GCC_C_SEQUENCE_SPEC +#define LINK_GCC_C_SEQUENCE_SPEC \ + "--start-group %G %L --end-group" Index: gcc/config.gcc =================================================================== --- gcc/config.gcc (revision 190922) +++ gcc/config.gcc (working copy) @@ -892,6 +892,10 @@ avr-*-rtems*) ;; avr-*-*) tm_file="elfos.h avr/elf.h avr/avr.h dbxelf.h avr/avr-stdint.h" + if test x${with_avrlibc} != xno; then + tm_file="${tm_file} ${cpu_type}/avrlibc.h" + tm_defines="${tm_defines} WITH_AVRLIBC" + fi tmake_file="avr/t-avr avr/t-multilib" use_gcc_stdint=wrap extra_gcc_objs="driver-avr.o avr-devices.o"