Hi all, I have been trying for a while now to upgrade tcl zu version 8.4.15 but I run into problem when compiling the file tclLoadDyld.c. The relevant error message is gcc -c -Os -O2 -pipe -I/opt/local/include -DTCL_DBGX= -Wall -Wno- implicit-int -fno-strict-aliasing -fno-common -I/opt/local/var/ macports/build/ _opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_tc l/work/tcl8.4.15/unix/../generic -I/opt/local/var/macports/build/ _opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_tc l/work/tcl8.4.15/unix -DNO_VALUES_H=1 -DHAVE_LIMITS_H=1 - DHAVE_UNISTD_H=1 -DHAVE_SYS_PARAM_H=1 -DHAVE_COREFOUNDATION=1 - DMAC_OSX_TCL=1 -DTCL_WIDE_INT_TYPE=long\ long -DWORDS_BIGENDIAN=1 - DHAVE_GETCWD=1 -DHAVE_OPENDIR=1 -DHAVE_STRSTR=1 -DHAVE_STRTOL=1 - DHAVE_STRTOLL=1 -DHAVE_STRTOULL=1 -DHAVE_TMPNAM=1 -DHAVE_WAITPID=1 - DHAVE_SYS_TIME_H=1 -DTIME_WITH_SYS_TIME=1 -DHAVE_TM_ZONE=1 - DHAVE_GMTIME_R=1 -DHAVE_LOCALTIME_R=1 -DHAVE_TM_GMTOFF=1 - DHAVE_ST_BLKSIZE=1 -DSTDC_HEADERS=1 -DHAVE_SIGNED_CHAR=1 - DHAVE_PUTENV_THAT_COPIES=1 -DHAVE_LANGINFO=1 -DHAVE_COPYFILE=1 - DHAVE_LIBKERN_OSATOMIC_H=1 -DHAVE_OSSPINLOCKLOCK=1 - DHAVE_PTHREAD_ATFORK=1 -DUSE_VFORK=1 -DTCL_DEFAULT_ENCODING=\"utf-8\" -DTCL_LOAD_FROM_MEMORY=1 -DHAVE_AVAILABILITYMACROS_H=1 -DHAVE_FTS=1 - DHAVE_SYS_IOCTL_H=1 -DHAVE_SYS_FILIO_H=1 -DTCL_SHLIB_EXT= \".dylib\" /opt/local/var/macports/build/ _opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_tc l/work/tcl8.4.15/unix/tclLoadDyld.c In file included from /opt/local/var/macports/build/ _opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_tc l/work/tcl8.4.15/unix/tclLoadDyld.c:23: /opt/local/include/mach-o/arch.h:35: error: nested redefinition of 'enum NXByteOrder' /opt/local/include/mach-o/arch.h:35: error: redeclaration of 'enum NXByteOrder' /opt/local/include/mach-o/arch.h:36: error: redeclaration of enumerator 'NX_UnknownByteOrder' /usr/include/architecture/byte_order.h:137: error: previous definition of 'NX_UnknownByteOrder' was here /opt/local/include/mach-o/arch.h:37: error: redeclaration of enumerator 'NX_LittleEndian' /usr/include/architecture/byte_order.h:138: error: previous definition of 'NX_LittleEndian' was here /opt/local/include/mach-o/arch.h:39: error: redeclaration of enumerator 'NX_BigEndian' /usr/include/architecture/byte_order.h:140: error: previous definition of 'NX_BigEndian' was here make: *** [tclLoadDyld.o] Error 1 Warning: the following items did not execute (for tcl): org.macports.activate org.macports.build org.macports.destroot org.macports.install Error: Status 1 encountered during processing. Apparently I get problems because gcc looks also at files in /usr/ include not only in /opt/local/include. Why is that and how can I prevent it? Thanks for your help. Joerg