I am trying to compile emacs-24.4 within Windows Bash (WinBash? Win-Bash?) however running into a problem that windows seems to have memory protection enabled which breaks the emacs build.
The error I get after 'make' (./configure works fine) is:
Dumping under the name emacs
**************************************************
Warning: Your system has a gap between BSS and the
heap (25164600 bytes). This usually means that exec-shield
or something similar is in effect. The dump may
fail because of this. See the section about
exec-shield in etc/PROBLEMS for more information.
**************************************************
/bin/bash: line 7: 6853 Segmentation fault (core dumped) ./temacs --batch --load loadup bootstrap
make[1]: *** [bootstrap-emacs] Error 1
make[1]: Leaving directory `/home/tdwyer/bin/emacs-24.5_linux_build/src'
make: *** [src] Error 2
In the etc/PROBLEMS file, the relevant section gives:
*** Segfault during `make bootstrap' under the Linux kernel.
In Red Hat Linux kernels, "Exec-shield" functionality is enabled by
default, which creates a different memory layout that can break the
emacs dumper. Emacs tries to handle this at build time, but if this
fails, the following instructions may be useful.
Exec-shield is enabled on your system if
cat /proc/sys/kernel/exec-shield
prints a value other than 0. (Please read your system documentation
for more details on Exec-shield and associated commands.)
Additionally, Linux kernel versions since 2.6.12 randomize the virtual
address space of a process by default. If this feature is enabled on
your system, then
cat /proc/sys/kernel/randomize_va_space
prints a value other than 0.
When these features are enabled, building Emacs may segfault during
the execution of this command:
./temacs --batch --load loadup [dump|bootstrap]
To work around this problem, you can temporarily disable these
features while building Emacs. You can do so using the following
commands (as root). Remember to re-enable them when you are done,
by echoing the original values back to the files.
echo 0 > /proc/sys/kernel/exec-shield
echo 0 > /proc/sys/kernel/randomize_va_space
Or, on x86, you can try using the `setarch' command when running
temacs, like this:
setarch i386 -R ./temacs --batch --load loadup [dump|bootstrap]
or
setarch i386 -R make
(The -R option disables address space randomization.)
And, unsurprisingly, if I look to see if it is enabled .. it is:
$ cat /proc/sys/kernel/randomize_va_space
2
But unfortunately, I try to disable it (even running bash as administrator), it fails:
$ sudo echo 0 > /proc/sys/kernel/randomize_va_space
bash: /proc/sys/kernel/randomize_va_space: Permission denied
Furthermore, setarch doesn't work using:
setarch x86_84 -R make
Suggestions?
