Here is the output from gdb for one of my numerous reproducible core dumps. Unfortunately, I cannot send the R code because it involves a lot of data setting up and a special order of calling my ehr function in my event library. Note that I am using 63.3 and not calling any of my own C or Fortran. Jim GNU gdb 4.17.0.4 with Linux/x86 hardware watchpoint and FPU support Copyright 1998 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i386-redhat-linux"... Core was generated by `/usr/local/src/R/bin/R.binary --no-save --no-restore --nsize 1M --vsize 12M'. Program terminated with signal 11, Segmentation fault. Reading symbols from /usr/X11R6/lib/libSM.so.6...done. Reading symbols from /usr/X11R6/lib/libICE.so.6...done. Reading symbols from /usr/X11R6/lib/libX11.so.6...done. Reading symbols from /usr/lib/libf2c.so.0...done. Reading symbols from /usr/lib/libreadline.so.3...done. Reading symbols from /lib/libdl.so.2...done. Reading symbols from /usr/lib/libncurses.so.4...done. Reading symbols from /lib/libm.so.6...done. Reading symbols from /lib/libc.so.6...done. Reading symbols from /lib/libtermcap.so.2...done. Reading symbols from /lib/ld-linux.so.2...done. Reading symbols from /usr/local/src/R/library/rmutil/libs/rmutil.so...done. Reading symbols from /usr/local/src/R/library/event/libs/event.so...done. #0 0x8080d6c in markSExp (s=Cannot access memory at address 0xbfffede4. ) at memory.c:501 501 if (s && !MARK(s)) { -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._