X-Git-Url: http://git.hcoop.net/bpt/emacs.git/blobdiff_plain/8f9d49058212da0396f8c4206b0628395ada6779..f1625eaa20d8b2d43bc7f0a439129eeab4d5948b:/configure.in

diff --git a/configure.in b/configure.in
index b7318b8f80..519f826f27 100644
--- a/configure.in
+++ b/configure.in
@@ -1286,6 +1286,7 @@ AC_LINK_IFELSE([main(){return 0;}],
 dnl checks for Unix variants
 AC_AIX
 
+
 #### Extract some information from the operating system and machine files.
 
 AC_CHECKING([the machine- and system-dependent files to find out
@@ -1571,6 +1572,53 @@ AH_TEMPLATE(POINTER_TYPE,
 	    [Define as `void' if your compiler accepts `void *'; otherwise
 	     define as `char'.])dnl
 
+dnl Test if heap start address is randomized (exec-shield does this).
+dnl The test program requires unistd.h and stdlib.h.  They are present
+dnl on the systems that currently have exec-shield.
+AC_MSG_CHECKING(whether heap start address is randomized)
+if test x"$ac_cv_header_unistd_h" != x && test x"$ac_cv_header_stdlib_h" != x
+then
+  AC_TRY_RUN([#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+int main (int argc, char *argv[])
+{
+  unsigned long old_sbrk = 0;
+  unsigned long this_sbrk = (unsigned long) sbrk(0);
+  int nr = 1;
+  if (argc != 1) {
+    old_sbrk = strtoul (argv[1], 0, 0);
+    nr = atoi (argv[2])+1;
+  }
+  if (argc == 1 || (old_sbrk == this_sbrk && nr < 3))
+  {
+    char buf1[32], buf2[32];
+    sprintf (buf1, "%lu", this_sbrk);
+    sprintf (buf2, "%d", nr);
+    execl (argv[0], argv[0], buf1, buf2, 0);
+    exit (-1);
+  }
+  exit (this_sbrk == old_sbrk);
+}], emacs_cv_randomheap=yes, emacs_cv_randomheap=no,
+     emacs_cv_randomheap='assuming no')
+else
+  emacs_cv_randomheap='assuming no'
+fi
+AC_MSG_RESULT($emacs_cv_randomheap)
+
+if test "$emacs_cv_randomheap" = yes; then
+  AC_PATH_PROG(SETARCH, setarch, no)
+  AC_SUBST(SETARCH)
+  if test "$SETARCH" != no && test "$machine" = "intel386"; then
+    AC_DEFINE(HAVE_RANDOM_HEAPSTART, 1,
+    [Define to 1 if this OS randomizes the start address of the heap.])
+  else
+    dnl We do the warning at the end of the configure run so it is seen.
+    emacs_cv_randomheap=warn
+  fi
+fi
+
+
 dnl This could be used for targets which can have both byte sexes.
 dnl We could presumably replace the hardwired WORDS_BIG_ENDIAN generally.
 dnl AC_C_BIGENDIAN
@@ -2265,6 +2313,9 @@ if test "${with_carbon}" != "no"; then
   AC_CHECK_HEADER(Carbon/Carbon.h, HAVE_CARBON=yes)
 fi
 
+dnl Check for malloc/malloc.h on darwin
+AC_CHECK_HEADER(malloc/malloc.h, AC_DEFINE(HAVE_MALLOC_MALLOC_H, 1, [Define to 1 if you have the <malloc/malloc.h> header file.]))
+
 if test "${HAVE_CARBON}" = "yes"; then
   AC_DEFINE(HAVE_CARBON, 1, [Define to 1 if you are using the Carbon API on Mac OS X.])
   window_system=mac
@@ -2342,7 +2393,7 @@ utimes setrlimit setpgid getcwd getwd shutdown getaddrinfo \
 __fpending mblen mbrlen mbsinit strsignal setitimer ualarm index rindex \
 sendto recvfrom getsockopt setsockopt getsockname getpeername \
 gai_strerror mkstemp getline getdelim mremap memmove fsync bzero \
-memset memcmp memmove difftime memcpy mempcpy mblen mbrlen posix_memalign)
+memset memcmp difftime memcpy mempcpy mblen mbrlen posix_memalign)
 
 AC_CHECK_HEADERS(sys/un.h)
 
@@ -3038,6 +3089,19 @@ echo "  Does Emacs use -lpng?                                   ${HAVE_PNG}"
 echo "  Does Emacs use X toolkit scroll bars?                   ${USE_TOOLKIT_SCROLL_BARS}"
 echo
 
+if test "$emacs_cv_randomheap" = warn; then 
+  AC_MSG_WARN([
+**********************************************************************
+
+Heap start address is randomized and no workaround is known.
+Emacs will probably dump core when temacs is run in the build phase.
+Maybe exec-shield is turned on.  Read about exec-shield in `etc/PROBLEMS'
+for further information.
+
+**********************************************************************
+])
+fi
+
 # Remove any trailing slashes in these variables.
 [test "${prefix}" != NONE &&
   prefix=`echo "${prefix}" | sed 's,\([^/]\)/*$,\1,'`