bin: add support for SPOT_OOM_ABORT

* bin/common_setup.cc: Here.
* NEWS, bin/man/spot-x.x: Document it.

NEWS

@@ -65,6 +65,10 @@ New in spot 2.4.2.dev (not yet released)
     by their acceptance name (Buchi, co-Buchi, Streett, etc.) or
     "other" if no name is known for the acceptance condition.
 
+  - All tools learned to check the SPOT_OOM_ABORT environment
+    variable.  This is only useful for debuging out-of-memory
+    conditions; see the spot-x(7) man page for detail.
+
   Library:
 
   - Rename three methods of spot::scc_info. New names are clearer. The

bin/common_setup.cc

@@ -79,6 +79,14 @@ static void setup_sig_handler()
 # define setup_sig_handler() while (0);
 #endif
 
+
+static void bad_alloc_handler()
+{
+  std::set_new_handler(nullptr);
+  std::cerr << "not enough memory\n";
+  abort();
+}
+
 void
 setup(char** argv)
 {
@@ -91,6 +99,9 @@ setup(char** argv)
 
   argp_err_exit_status = 2;
 
+  if (getenv("SPOT_OOM_ABORT"))
+    std::set_new_handler(bad_alloc_handler);
+
   std::ios_base::sync_with_stdio(false);
   // Do not flush std::cout every time we read from std::cin, unless
   // we are reading from a terminal.  Note that we do flush regularly

bin/man/spot-x.x

@@ -99,6 +99,19 @@ in third-party tools that output incorrect HOA (e.g., declaring
 the automaton with property "univ-branch" when no universal branching
 is actually used)
 
+.TP
+\fBSPOT_OOM_ABORT\fR
+If this variable is set, Out-Of-Memory errors will \f(CWabort()\fR the
+program (potentially generating a coredump) instead of raising an
+exception.  This is useful to debug a program and to obtain a stack
+trace pointing to the function doing the allocation.  When this
+variable is unset (the default), \f(CWstd::bad_alloc\fR are thrown on
+memory allocation failures, and the stack is usually unwinded up to
+top-level, losing the original context of the error.  Note that at
+least \f(CWltlcross\fR has some custom handling of
+\f(CWstd::bad_alloc\fR to recover from products that are too large (by
+ignoring them), and setting this variable will interfer with that.
+
 .TP
 \fBSPOT_PR_CHECK\fR
 Select the default algorithm that must be used to check the persistence