Re: gcc-4.7.1 build system question : why is "make bootstrap" with configure option '--enable-languages=c' building the C++ compiler ?

Re: gcc-4.7.1 build system question : why is "make bootstrap" with configure option '--enable-languages=c' building the C++ compiler ?

[Jonathan Wakely]

Hi,

The gcc-bugs mailing list is for automated emails from our Bugzilla
database.  Your question is not about a bug, so would be more
appropriate on the gcc-help mailing list.

The answer to your question is that GCC itself is now built using a
C++ compiler, so it needs to build the C++ compiler to build itself,
see http://gcc.gnu.org/install/configure.html

--enable-build-poststage1-with-cxx
    When bootstrapping, build stages 2 and 3 of GCC using a C++
compiler rather than a C compiler. Stage 1 is still built with a C
compiler. This is enabled by default and may be disabled using
--disable-build-poststage1-with-cxx.

Re: gcc-4.7.1 build system question : why is "make bootstrap" with configure option '--enable-languages=c' building the C++ compiler ?

[Jason Vas Dias]

OK, so I'm reconfiguring with :
    --enable-languages=c --disable-build-with-cxx
--disable-build-poststage1-with-cxx --enable-stage1-checking=all
--enable-stage1-languages=c
but why should I have to ? Shouldn't "--enable-languages=c" be enough
to disable building the C++ compiler and libstdc++ ?
Thanks & Regards,
 Jason

On Sun, Jul 8, 2012 at 4:06 PM, Jason Vas Dias <jason.vas.dias@gmail.com> wrote:
> Hi -  I've been regularly building gcc for nearly two decades, and now
> attempting to build a bootstrap
> "C" only gcc-4.7.1 sufficient only to build binutils (my initial first
> step is always to rebuild binutils
> with the bootstrap "C" only compiler before doing a complete "make"
> with "--enable-languages=all" -
> a shame that support for configuring and building binutils along with
> gcc has been withdrawn ,
> so now I attempt to rebuild binutils separately with the "C" only
> bootstrap compiler) .
>
> Now this doesn't work - building "C"-only ( --enable-languages=c )
> bootstrap fails building "C++" :
>
> /mnt/sda3/gcc/./prev-gcc/g++ -B/mnt/sda3/gcc/./prev-gcc/
> -B/usr/x86_64-pc-linux-gnu/bin/ -nostdinc++
> -B/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
> -B/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
> -I/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
> -I/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/include
> -I/usr/build2/gcc/gcc-4.7.1/libstdc++-v3/libsupc++
> -L/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
> -L/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
>  -g -O2 -gtoggle -DIN_GCC   -fno-exceptions -fno-rtti -W -Wall
> -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute
> -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings
>  -DHAVE_CONFIG_H -static-libstdc++ -static-libgcc  -o cc1 c-lang.o
> c-family/stub-objc.o attribs.o c-errors.o c-decl.o c-typeck.o
> c-convert.o c-aux-info.o c-objc-common.o c-parser.o tree-mudflap.o
> c-family/c-common.o c-family/c-cppbuiltin.o c-family/c-dump.o
> c-family/c-format.o c-family/c-gimplify.o c-family/c-lex.o
> c-family/c-omp.o c-family/c-opts.o c-family/c-pch.o
> c-family/c-ppoutput.o c-family/c-pragma.o c-family/c-pretty-print.o
> c-family/c-semantics.o c-family/c-ada-spec.o i386-c.o default-c.o \
>   cc1-checksum.o main.o  libbackend.a libcommon-target.a libcommon.a
> ../libcpp/libcpp.a ../libdecnumber/libdecnumber.a libcommon.a
> ../libcpp/libcpp.a   ../libiberty/libiberty.a
> ../libdecnumber/libdecnumber.a  -lcloog -lppl_c -lppl -lpwl -lgmpxx
> -lmpc -lmpfr -lgmp -rdynamic -ldl  -lz
> lto/lto.o: In function `lto_ft_typed(tree_node*)':
> lto.c:(.text+0x326): undefined reference to `tree_code_type'
> lto/lto.o: In function `lto_ft_common(tree_node*)':
> lto.c:(.text+0x38b): undefined reference to `tree_code_type'
> lto/lto.o: In function `lto_ft_decl_common(tree_node*)':
> lto.c:(.text+0x3fb): undefined reference to `tree_code_type'
> lto.c:(.text+0x432): undefined reference to `tree_code_type'
> lto.c:(.text+0x469): undefined reference to `tree_code_type'
> lto/lto.o:lto.c:(.text+0x49e): more undefined references to
> `tree_code_type' follow
>
> Boy, does it really mean it when it says "more undefined references to
> `tree_code_type' follow" :
>
>  $ grep 'undefined reference' make.bootstrap-cntnd.log  | wc -l
> 18127
>
> My config.log command :
>
>
>  generated by GNU Autoconf 2.64.  Invocation command line was
>
>   $ /usr/build2/gcc/gcc-4.7.1/configure --prefix=/usr
> --libdir=/usr/lib64 --with-cpu-32=i686 --with-cpu-64=k8
> --enable-languages=c --enable-targets=all --enable-multi
> lib --enable-threads=posix --enable-tls --enable-lto --enable-shared
> --enable-checking=release --with-build-time-tools=/usr/bin
> --with-ld=/usr/bin/ld --with-gnu-ld --
> with-as=/usr/bin/as --with-gnu-as
> --enable-version-specific-runtime-libs --with-system-zlib
> --without-included-gettext --enable-bootstrap
> --enable-serial-configure --
> host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu
>
> ## --------- ##
> ## Platform. ##
> ## --------- ##
>
> hostname = jvdspc
> uname -m = x86_64
> uname -r = 3.4.4-jvd+
> uname -s = Linux
> uname -v = #4 SMP Fri Jul 6 20:19:44 GMT 2012
>
> /usr/bin/uname -p = unknown
> /bin/uname -X     = unknown
>
> /bin/arch              = x86_64
> /usr/bin/arch -k       = unknown
> /usr/convex/getsysinfo = unknown
> /usr/bin/hostinfo      = unknown
> /bin/machine           = unknown
> /usr/bin/oslevel       = unknown
> /bin/universe          = unknown
>
> I configured with above command and did:
>
> $ make -j2 bootstrap 2>&1 | tee make.bootstrap.log
>
> This built fine overnight , and when I woke up in the morning the
> machine was in a hard lock-up state
> (overheating - I'm also investigating a kernel bug on this issue).
>
> The build had created the "stage_final" file and a working prev-gcc/xgcc -
> Can anyone suggest why making a "bootstrap" "C" "--enable-languages=c"
> compiler should then
> go on to build "C++" ?
>
> I'm pretty sure the above error would not have occurred without the
> kernel lock-up and interruption,
> but nevertheless,  I didn't ask the gcc build system to build C++ yet,
> so why did it do so ?
>
> Any ideas / comments would be much appreciated ,
> Jason Vas Dias (a Software Engineer) <jason.vas.dias@gmail.com>

gcc-4.7.1 build system question : why is "make bootstrap" with configure option '--enable-languages=c' building the C++ compiler ?

[Jason Vas Dias]

Hi -  I've been regularly building gcc for nearly two decades, and now
attempting to build a bootstrap
"C" only gcc-4.7.1 sufficient only to build binutils (my initial first
step is always to rebuild binutils
with the bootstrap "C" only compiler before doing a complete "make"
with "--enable-languages=all" -
a shame that support for configuring and building binutils along with
gcc has been withdrawn ,
so now I attempt to rebuild binutils separately with the "C" only
bootstrap compiler) .

Now this doesn't work - building "C"-only ( --enable-languages=c )
bootstrap fails building "C++" :

/mnt/sda3/gcc/./prev-gcc/g++ -B/mnt/sda3/gcc/./prev-gcc/
-B/usr/x86_64-pc-linux-gnu/bin/ -nostdinc++
-B/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
-B/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
-I/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
-I/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/include
-I/usr/build2/gcc/gcc-4.7.1/libstdc++-v3/libsupc++
-L/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
-L/mnt/sda3/gcc/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
 -g -O2 -gtoggle -DIN_GCC   -fno-exceptions -fno-rtti -W -Wall
-Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute
-pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings
 -DHAVE_CONFIG_H -static-libstdc++ -static-libgcc  -o cc1 c-lang.o
c-family/stub-objc.o attribs.o c-errors.o c-decl.o c-typeck.o
c-convert.o c-aux-info.o c-objc-common.o c-parser.o tree-mudflap.o
c-family/c-common.o c-family/c-cppbuiltin.o c-family/c-dump.o
c-family/c-format.o c-family/c-gimplify.o c-family/c-lex.o
c-family/c-omp.o c-family/c-opts.o c-family/c-pch.o
c-family/c-ppoutput.o c-family/c-pragma.o c-family/c-pretty-print.o
c-family/c-semantics.o c-family/c-ada-spec.o i386-c.o default-c.o \
  cc1-checksum.o main.o  libbackend.a libcommon-target.a libcommon.a
../libcpp/libcpp.a ../libdecnumber/libdecnumber.a libcommon.a
../libcpp/libcpp.a   ../libiberty/libiberty.a
../libdecnumber/libdecnumber.a  -lcloog -lppl_c -lppl -lpwl -lgmpxx
-lmpc -lmpfr -lgmp -rdynamic -ldl  -lz
lto/lto.o: In function `lto_ft_typed(tree_node*)':
lto.c:(.text+0x326): undefined reference to `tree_code_type'
lto/lto.o: In function `lto_ft_common(tree_node*)':
lto.c:(.text+0x38b): undefined reference to `tree_code_type'
lto/lto.o: In function `lto_ft_decl_common(tree_node*)':
lto.c:(.text+0x3fb): undefined reference to `tree_code_type'
lto.c:(.text+0x432): undefined reference to `tree_code_type'
lto.c:(.text+0x469): undefined reference to `tree_code_type'
lto/lto.o:lto.c:(.text+0x49e): more undefined references to
`tree_code_type' follow

Boy, does it really mean it when it says "more undefined references to
`tree_code_type' follow" :

 $ grep 'undefined reference' make.bootstrap-cntnd.log  | wc -l
18127

My config.log command :


 generated by GNU Autoconf 2.64.  Invocation command line was

  $ /usr/build2/gcc/gcc-4.7.1/configure --prefix=/usr
--libdir=/usr/lib64 --with-cpu-32=i686 --with-cpu-64=k8
--enable-languages=c --enable-targets=all --enable-multi
lib --enable-threads=posix --enable-tls --enable-lto --enable-shared
--enable-checking=release --with-build-time-tools=/usr/bin
--with-ld=/usr/bin/ld --with-gnu-ld --
with-as=/usr/bin/as --with-gnu-as
--enable-version-specific-runtime-libs --with-system-zlib
--without-included-gettext --enable-bootstrap
--enable-serial-configure --
host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu

## --------- ##
## Platform. ##
## --------- ##

hostname = jvdspc
uname -m = x86_64
uname -r = 3.4.4-jvd+
uname -s = Linux
uname -v = #4 SMP Fri Jul 6 20:19:44 GMT 2012

/usr/bin/uname -p = unknown
/bin/uname -X     = unknown

/bin/arch              = x86_64
/usr/bin/arch -k       = unknown
/usr/convex/getsysinfo = unknown
/usr/bin/hostinfo      = unknown
/bin/machine           = unknown
/usr/bin/oslevel       = unknown
/bin/universe          = unknown

I configured with above command and did:

$ make -j2 bootstrap 2>&1 | tee make.bootstrap.log

This built fine overnight , and when I woke up in the morning the
machine was in a hard lock-up state
(overheating - I'm also investigating a kernel bug on this issue).

The build had created the "stage_final" file and a working prev-gcc/xgcc -
Can anyone suggest why making a "bootstrap" "C" "--enable-languages=c"
compiler should then
go on to build "C++" ?

I'm pretty sure the above error would not have occurred without the
kernel lock-up and interruption,
but nevertheless,  I didn't ask the gcc build system to build C++ yet,
so why did it do so ?

Any ideas / comments would be much appreciated ,
Jason Vas Dias (a Software Engineer) <jason.vas.dias@gmail.com>