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Re: system inc and dynamic linker change
Hi,
seems like I got it working the way I wanted it, this is what I did:
(On Suse linux 8 with glibc 2.2)
Configure, compile and install glibc-2.3.5 into /opt23
--------------------------
Configure and compile binutils against glibc-2.3.5 headers, then in the
binutils src dir:
find . -name Makefile -a -exec grep -q "^LDFLAGS[[:space:]]*=" '{}' \; -a
-print | while read i ; do mv $i $i.ori ; cat $i.ori | awk --
'/^LDFLAGS[[:space:]]*=[[:space:]]*$/ { print "LDFLAGS = -B /opt23/lib
-Wl,-rpath-link,/opt23/lib,--dynamic-linker,/opt23/lib/ld-linux.so.2";
}\
! /^LDFLAGS[[:space:]]*=[[:space:]]*$/ { print }' > $i ; done
Now I ran "make" again, then "make install"
This way I got as,ld,ar,... linked with new glibc.
---------------------------
For gcc, first I edited "gcc-3.4.4/gcc/config/i386/linux.h" file in the
gcc source directory and replaced:
%{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2}}
with:
%{!dynamic-linker:-dynamic-linker /opt23/lib/ld-linux.so.2}}
Set CFLAGS, CXXFLAGS to:
"-B /opt23/bin -B /opt23/lib -isystem /opt23/usr/include"
In the build directory I ran:
"../gcc-3.4.4/configure --with-sysroot=/opt23
--enable-threads=posix --prefix=/opt23"
Then edited the created Makefile to change:
LDFLAGS =
into
LDFLAGS = -B /opt23/lib
-Wl,-rpath-link,/opt23/lib,--dynamic-linker,/opt23/lib/ld-linux.so.2
Now a quick "make", "make install" and I got myself a gcc in /opt23/bin
(need to put it into first place of $PATH) that creates executables that
are linked against /opt23/lib/ld-linux.so.2 and /opt23/lib/libc.so.6
$ gcc -o test test.c
$ ldd ./test
libc.so.6 => /opt23//lib/libc.so.6 (0x4001b000)
/opt23/lib/ld-linux.so.2 (0x40000000)
I tested moving /opt/include/stdio.h away, gcc cannot find it anymore, so
it searches system headers at the new place.
Of course I need to test it further.
Why is it that the configure script for gcc-3.4.4 creates a Makefile that
destroys the LDFLAGS env variable ?
Now I'm going to try and build some real programs...
bye, krajo
On Thu, 15 Sep 2005, Aseem Rastogi wrote:
did you try compiling gcc itself with -Wl,--dynamic-linker ? the new gcc then
should then default link to ur custom glibc. also, if you can find some
solution to shared library problem that i mentioned, it would be very
helpful.
aseem.
KRAJCSOVITS Gyorgy wrote:
Hi, thanks for the reply,
yes -Wl,--dynamic-linker works, but when I'm compiling big programs it is
sometimes impossible (ok, very hard) to change the linker for every link
step. It would be better to have gcc (or ld) automatically do this.
And I need gcc to search other directories for system header files as
well.
bye, krajo
On Thu, 15 Sep 2005, Aseem Rastogi wrote:
i am not sure about existing application but for a new program
-Wl,--dynamic-linker option works. i successfully did it for simple hello
world kind of programs but when i created shared libraries using this
option, it didn;t work and they seemed to be linked to default linker.
try compiling gcc with this option to escape --dynamic-linker everytime.
regards,
aseem.
KRAJCSOVITS Gyorgy wrote:
Hi,
I'd like to compile a gcc that uses:
- /opt23/usr/include instead of /usr/include
(and similar for other system include dirs)
- instructs linker to use /opt23/lib/ld-linux.so.2 instead of
/lib/ld-linux.so.2
(Maybe this is a binutils issue, but it seems like binutils gets its
deafults from gcc when compiling binutils)
The idea is to be able to compile programs for another glibc, but I'm not
root, so I won't be able to use it in it's normal location. So
/lib/ld-linux.so.2 won't point to the new one. I tried to create a cross
compile toolchain but was unsuccessfull so far.
Is there a way to change the dynamic linker of an existing application ?
From /lib/ld-linux.so.2 to /opt23/lib/ld-linux.so.2 ?
bye, krajo
--
The end is always good. If it's not good, it's not the end.
--
The end is always good. If it's not good, it's not the end.