Dear specialists, I tried to compile gcc 4.8.5 using gcc 8.1.1. First I added some lines to gcc-4.8.5/gcc/cp/cfns.{gperf,h} as somewhere suggests. 19 #ifdef __GNUC__ 20 __inline 21 #endif 22 static unsigned int hash (const char *, unsigned int); 23 #ifdef __GNUC__ 24 __inline 25 #ifdef __GNUC_STDC_INLINE__ 26 __attribute__ ((__gnu_inline__)) 27 #endif 28 #endif 29 const char * libc_name_p (const char *, unsigned int); Then I run "./configure --prefix=/home/rx/program/gcc-4.8.5/build --with-gmp=/home/rx/program/gmp-6.1.0 --with-mpfr=/home/rx/program/mpfr-3.1.4 --disable-multilib --enable-languages=c,c++,fortran --disable-stage1-checking" But, there are still some errors as below. Fixed: X11/Xw32defs.h Applying io_quotes_use to sys/mount.h Applying io_quotes_use to sys/raw.h Cleaning up unneeded directories: fixincludes is done echo timestamp > stmp-fixinc make[3]: Leaving directory '/home/rx/program/gcc-4.8.5/host-x86_64-unknown-linux-gnu/gcc' make[2]: *** [Makefile:4157: all-stage1-gcc] Error 2 make[2]: Leaving directory '/home/rx/program/gcc-4.8.5' make[1]: *** [Makefile:19785: stage1-bubble] Error 2 make[1]: Leaving directory '/home/rx/program/gcc-4.8.5' make: *** [Makefile:886: all] Error 2 Am I still missing something? Thank you. Regards, Jianhao