Solaris

               export CC=cc
               export CFLAGS="-m64"
               export CPPFLAGS="-m64"

       ./Configure -Dcc=${CMP_ROOT}/opt/SUNWspro/bin/CC -Accflags="-m64"        -Dprefix=/mpde/sun10.x/perl/test/5.8.9 -Dusethreads

      CC: Warning: -xarch=generic64 is deprecated, use -m64 to create       64-bit programs
      CC: Warning: -xarch=generic64 is deprecated, use -m64 to create       64-bit programs
      Your double is 8 bytes long.

      "Finding dependencies for walk.o.
      make: Warning: Both `makefile' and `Makefile' exist
      Current working directory       /home/mpde/gnu/perl/perl-5.8.9/perl-5.8.9/x2p
      echo Makefile.SH cflags.SH | tr ' ' '\n' >.shlist
      Updating makefile...
      /bin/sh config_h.SH
      Extracting config.h (with variable substitutions)
      `sh  cflags "optimize='-O'" miniperlmain.o`  miniperlmain.c
                CCCMD =  /mpde/sun10.x/cmplrs/CC_5.9/opt/SUNWspro/bin/CC        -DPERL_CORE -c -D_REENTRANT -m64 -I/usr/local/include -m64        -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -DPERL_USE_SAFE_PUTENV         -O  
      "proto.h", line 31: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 41: Warning: attribute __malloc__ is unsupported       and will be skipped..
      "proto.h", line 42: Error: "{" expected instead of "(".
      "proto.h", line 42: Error: warn_unused_result is not defined.
      "proto.h", line 44: Error: Linkage specifications are allowed only       at file level.
      "proto.h", line 45: Warning: attribute __malloc__ is unsupported       and will be skipped..
      "proto.h", line 46: Error: "," expected instead of "(".
      "proto.h", line 48: Error: Linkage specifications are allowed only       at file level.
      "proto.h", line 230: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 231: Error: "{" expected instead of "(".
      "proto.h", line 231: Error: pure is not defined.
      "proto.h", line 233: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 234: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 235: Error: "," expected instead of "(".
      "proto.h", line 237: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 238: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 239: Error: "," expected instead of "(".
      "proto.h", line 241: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 242: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 243: Error: "," expected instead of "(".
      "proto.h", line 245: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 246: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 247: Error: "," expected instead of "(".
      "proto.h", line 249: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 250: Warning: attribute warn_unused_result is       unsupported and will be skipped..
      "proto.h", line 252: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 255: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 256: Error: Linkage specifications are allowed       only at file level.
      "proto.h", line 257: Error: Linkage specifications are allowed       only at file level.
      Compilation aborted, too many Error messages.
      *** Error code 1
      make: Fatal error: Command failed for target `miniperlmain.o'"