Hi, I just discovered a nasty problem with the latest CVS Autoconf on Red Hat Linux v7 (default setup, i.e. with g++ 2.96). In short, the AC_TRY_COMPILE in the configure.in script below will fail: ->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8-- AC_INIT(configure.in) AC_LANG_CPLUSPLUS AC_TRY_COMPILE([#include <stdlib.h>], [], , AC_MSG_ERROR(sorr-ee)) AC_OUTPUT() ->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8-- Here's the relevant part of config.log: ->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8-- [...] configure:1141: g++ -c -g -O2 conftest.cpp >&5 In file included from configure:1135: /usr/include/stdlib.h:578: declaration of `void exit (int) throw ()' throws different exceptions configure:1132: than previous declaration `void exit (int)' configure: failed program was: #line 1130 "configure" #include "confdefs.h" #ifdef __cplusplus extern "C" void exit (int); #endif #include <stdlib.h> int main () { ; return 0; } ->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8--->8-->8-- Now, this is obviously due to the "extern" forward declaration of exit() not matching the exit() defined by the stdlib.h of GCC 2.96 when run as a C++ compiler. Why is the explicit exit() declaration there anyway? Removing it will of course make the configure script run correctly. Regards, Morten