Added debug script to aid in getting crash callstacks from users.

scripts/linux_debug.pl

@@ -0,0 +1,24 @@
+#!/usr/bin/perl
+
+use strict;
+
+my $i; my $findResult;
+my $exe = "fceux";
+
+$findResult = `find . -name fceux`;
+
+if ( $findResult ne "")
+{
+   $findResult =~ s/\n.*//;
+   $exe=$findResult;
+}
+print "Executable: $exe\n";
+
+my $gdbCmdFile = "/tmp/gdbCmdFile";
+open CMD_FILE, ">$gdbCmdFile" or die "Error: Could not open file: $gdbCmdFile\n";
+print CMD_FILE "run\n";
+print CMD_FILE "backtrace\n";
+close(CMD_FILE);
+
+system("gdb  -x $gdbCmdFile  $exe");
+

src/types.h

@@ -160,6 +160,7 @@ typedef uint8 (*readfunc)(uint32 A);
 #endif
 
 #define  FCEU_UNUSED(x)   (void)(x)
+#define  FCEU_CRASH()     int *_dumbPointer = nullptr; *_dumbPointer = 0xdeadbeef
 
 #if FCEU_CPP_HAS_STD(201603L) || FCEU_HAS_CPP_ATTRIBUTE(maybe_unused)
 #define  FCEU_MAYBE_UNUSED  [[maybe_unused]]