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gcc configure: error: Building GCC requires GMP 4.2+, MPFR 2.3.1+ and MPC 0.8.0+

安装gmp:  ./configure --prefix=/usr/local/gmp-4.3.2; make install
安装mpfr: ./configure --prefix=/usr/local/mpfr-2.4.2 --with-gmp=/usr/local/gmp-4.3.2/; make install
安装mpc:  ./configure --prefix=/usr/local/mpc-0.8.1 --with-gmp=/usr/local/gmp-4.3.2/ --with-mpfr=/usr/local/mpfr-2.4.2/; make install

MPFR=mpfr-2.4.2
GMP=gmp-4.3.2
MPC=mpc-0.8.1

wget ftp://gcc.gnu.org/pub/gcc/infrastructure/$MPFR.tar.bz2 || exit 1
tar xjf $MPFR.tar.bz2 || exit 1
ln -sf $MPFR mpfr || exit 1

wget ftp://gcc.gnu.org/pub/gcc/infrastructure/$GMP.tar.bz2 || exit 1
tar xjf $GMP.tar.bz2  || exit 1
ln -sf $GMP gmp || exit 1

wget ftp://gcc.gnu.org/pub/gcc/infrastructure/$MPC.tar.gz || exit 1
tar xzf $MPC.tar.gz || exit 1
ln -sf $MPC mpc || exit 1

rm $MPFR.tar.bz2 $GMP.tar.bz2 $MPC.tar.gz || exit 1

echo $LD_LIBRARY_PATH

指定安装：export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/gmp-4.3.2/lib:/usr/local/mpfr-2.4.2/lib:/usr/local/mpc-0.8.1/lib

默认安装：export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

configure: error: cannot compute suffix of object files: cannot compile

/home/wulei/sourcecode/gcc-4.6.2/configure --prefix=/usr/local/gcc-4.6.2 --enable-threads=posix --disable-checking --disable-multilib --enable-languages=c --with-gmp=/usr/local/gmp-4.3.2/ --with-mpfr=/usr/local/mpfr-2.4.2/ --with-mpc=/usr/local/mpc-0.8.1/
最终用：../gcc-4.6.2/configure --prefix=/usr/gcc-4.6.9 --enable-threads=posix --disable-checking --disable-multilib --enable-languages=c --with-gmp=/usr/gmp-4.3.2 --with-mpfr=/usr/mpfr-2.4.2 --with-mpc=/usr/mpc-0.8.1

make
make check
make install

/usr/bin/ld: .libs/expat_justparse_interface.o: relocation R_X86_64_32 against `a local symbol' can not be used when making a shared object; recompile with -fPIC
.libs/expat_justparse_interface.o: could not read symbols: Bad value

make CXXFLAGS=-fPIC CFLAGS=-fPIC

Checking for suffix of object files... configure: error: in `/home/wulei/sourcecode/gcc-4.6.2/i686-pc-linux-gnu/libgcc':
configure: error: cannot compute suffix of object files: cannot compile
See `config.log' for more details.
make[2]: *** [configure-stage1-target-libgcc] 错误 1
make[2]:正在离开目录 `/home/wulei/sourcecode/gcc-4.6.2'
make[1]: *** [stage1-bubble] 错误 2
make[1]:正在离开目录 `/home/wulei/sourcecode/gcc-4.6.2'
make: *** [all] 错误 2

/home/wulei/sourcecode/gcc-4.6.2/host-i686-pc-linux-gnu/gcc/cc1: error while loading shared libraries: libmpfr.so.1: cannot open shared object file: No such file or directory

export LD_LIBRARY_PATH=/usr/local/mpc-0.8.1/lib:/usr/local/mpfr-2.4.2/lib:/usr/local/gmp-4.3.2/lib

./configure –prefix=/usr/local/supersparrow

/* 文件名：verifypasswd.c */
/* 这是一段判断用户口令的程序，其中使用到了标准C函数strcmp*/
#include <stdio.h>
#include <string.h>
int main(int argc, char **argv)
{
	char passwd[] = "password";
	if (argc < 2) {
		printf("usage: %s <password>/n", argv[0]);
		return 1;
	}
	if (!strcmp(passwd, argv[1])) {
		printf("Correct Password!/n");
		return 1;
	}
	printf("Invalid Password!/n");
	return 0;
}

/* 文件名：hack.c */
#include <stdio.h>

#include <string.h>
int strcmp(const char *s1, const char *s2)
{
	printf("hack function invoked. s1=<%s> s2=<%s>/n", s1, s2);
	/* 永远返回0，表示两个字符串相等 */
	return 0;
}

$ gcc -o verifypasswd verifypasswd.c
$ gcc -shared -o hack.so hack.c

$ ./verifypasswd asdf
Invalid Password!

$ export LD_PRELOAD="./hack.so"

$ ./verifypasswd  asdf
hack function invoked. s1=<password> s2=<asdf>
Correct Password!