singular: disable vspace on aarch64

pkgs/applications/science/math/singular/default.nix

@@ -52,6 +52,9 @@ stdenv.mkDerivation rec {
     # add aarch64 support to cpu-check.m4. copied from redhat.
     ./redhat-aarch64.patch
 
+    # vspace causes hangs in modstd and other libraries on aarch64
+    ./disable-vspace-on-aarch64.patch
+
     # the newest version of ax-prog-cc-for-build.m4 seems to trigger
     # linker errors. see
     # https://github.com/alsa-project/alsa-firmware/issues/3 for a

pkgs/applications/science/math/singular/disable-vspace-on-aarch64.patch

@@ -0,0 +1,15 @@
+diff --git a/kernel/mod2.h b/kernel/mod2.h
+index 867fcae47..2abd84f23 100644
+--- a/kernel/mod2.h
++++ b/kernel/mod2.h
+@@ -60,8 +60,10 @@
+ 
+ /* define for parallel processes with shared memory */
+ #ifndef __CCYGWIN__
++#ifndef SI_CPU_AARCH64
+ #define HAVE_VSPACE 1
+ #endif
++#endif
+ 
+ /*#define PROFILING*/
+ #ifdef PROFILING