> > hello, i have just upgraded to the latest version of redhat linux > > and suddenly my g++ compiled programs fall over.   > From your description, it was not clear whether the old binaries > stopped working on the new system, or whether binaries created on the > new system with the new compiler would break.   thank you for your help. old binaries still work. Only newly compiled ones coredump.   > Also, it is not clear to me whether you have installed the latest > redhat version "from scratch", or overwritten your previous > installation. It may well be that there were still some old files > lying around which should have been removed but weren't.   i have overwritten my previous (2 year old) installation.  i suspect that your analysis is correct. alas i am not familiar enough with the g++ library system to work out which files are the troublemakers. (btw: is there an easily accessible description of the structure of g++ and its libraries, or do i have to read the code/man pages to get the picture?)   > To investigate this further, please try the following commands:   > ldd > g++ -o -v --trace-includes   > rpm -qf   the output is quoted below.   thanks, martin   i am using redhat release 6.1, kernel 2.2.12.20. the output of ldd is:   --------------------------------------------------------------------------     libm.so.6 => /lib/libm.so.6 (0x40018000)   libc.so.6 => /lib/libc.so.6 (0x40035000)   /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)   --------------------------------------------------------------------------     lsl /lib/libm.so.6   lrwxrwxrwx   1 root     root           13 Mar 21 23:46 /lib/libm.so.6 -> libm-2.1.2.so   lsl /lib/libc.so.6   lrwxrwxrwx   1 root     root           13 Mar 21 23:46 /lib/libc.so.6 -> libc-2.1.2.so   lsl /lib/ld-linux.so.2   lrwxrwxrwx   1 root     root           11 Mar 21 23:46 /lib/ld-linux.so.2 -> ld-2.1.2.so     /lib> rpm -qf libm-2.1.2.so   glibc-2.1.2-11   /lib> rpm -qf libc-2.1.2.so   glibc-2.1.2-11   /lib> rpm -qf ld-2.1.2.so    glibc-2.1.2-11   the output of g++ with the aforementioned command line options is as follows. --------------------------------------------------------------------------     Reading specs from /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/specs   gcc version egcs-2.91.66 19990314 (egcs-1.1.2 release)   /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/cpp -lang-c++ -v -undef -D__GNUC__=2 -D__GNUG__=2 -D__cplusplus -D__GNUC_MINOR__=91 -D__ELF__ -Dunix -Di386 -D__i386__ -Dlinux -D__ELF__ -D__unix__ -D__i386__ -D__i386__ -D__linux__ -D__unix -D__i386 -D__linux -Asystem(posix) -D__EXCEPTIONS -H -Asystem(unix) -Acpu(i386) -Amachine(i386) -Di386 -D__i386 -D__i386__ -Di586 -Dpentium -D__i586 -D__i586__ -D__pentium -D__pentium__ test.cpp /tmp/ccBN0ncc.ii   GNU CPP version egcs-2.91.66 19990314 (egcs-1.1.2 release) (i386 Linux/ELF)   #include "..." search starts here:   #include <...> search starts here:    /usr/local/include/g++    /usr/local/include    /usr/local/i586-pc-linux-gnu/include    /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/include    /usr/include   End of search list.   /usr/local/include/g++/iostream    /usr/local/include/g++/iostream.h     /usr/local/include/g++/streambuf.h      /usr/include/libio.h       /usr/include/_G_config.h        /usr/include/bits/types.h         /usr/include/features.h          /usr/include/sys/cdefs.h          /usr/include/gnu/stubs.h         /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/include/stddef.h        /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/include/stddef.h       /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/include/stdarg.h      /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/include/stdarg.h    /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/cc1plus /tmp/ccBN0ncc.ii -quiet -dumpbase test.cc -version -o /tmp/ccIKwR7h.s   GNU C++ version egcs-2.91.66 19990314 (egcs-1.1.2 release) (i586-pc-linux-gnu) compiled by GNU C version egcs-2.91.66 19990314 (egcs-1.1.2 release).    as -V -Qy -o /tmp/ccVMJY2e.o /tmp/ccIKwR7h.s   GNU assembler version 2.9.1 (i386-redhat-linux), using BFD version 2.9.1.0.24    /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/collect2 -m elf_i386 -dynamic-linker /lib/ld-linux.so.2 -o a.out /usr/lib/crt1.o /usr/lib/crti.o /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/crtbegin.o -L/usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66 -L/usr/local/i586-pc-linux-gnu/lib -L/usr/local/lib /tmp/ccVMJY2e.o -lstdc++ -lm -lgcc -lc -lgcc /usr/local/lib/gcc-lib/i586-pc-linux-gnu/egcs-2.91.66/crtend.o /usr/lib/crtn.o Â