Patch backported from
https://github.com/vdudouyt/mhddfs-nosegfault

Thanks to Gabor Kovari <gabor.kovari@gmail.com>

--- a/src/main.c	2012-06-17 16:09:56.000000000 +0200
+++ b/src/main.c	2015-12-21 16:32:29.000000000 +0100
@@ -33,6 +33,13 @@
 #include <sys/time.h>
 #include <utime.h>
 
+#include <execinfo.h>
+#include <signal.h>
+#include <unistd.h>
+
+#include <glib.h>
+#include <sys/resource.h>
+
 #ifndef WITHOUT_XATTR
 #include <attr/xattr.h>
 #endif
@@ -42,7 +49,21 @@
 
 #include "debug.h"
 
-#include <uthash.h>
+void save_backtrace(int sig)
+{
+  void *array[10];
+  size_t size;
+
+  // get void*'s for all entries on the stack
+  size = backtrace(array, 10);
+
+  // print out all the frames to stderr
+  fprintf(stderr, "Error: signal %d\n", sig);
+  FILE *log = fopen("/tmp/mhddfs_backtrace.log", "w");
+  backtrace_symbols_fd(array, size, fileno(log));
+  fclose(log);
+  exit(1);
+}
 
 // getattr
 static int mhdd_stat(const char *file_name, struct stat *buf)
@@ -161,16 +182,13 @@
 	mhdd_debug(MHDD_MSG, "mhdd_readdir: %s\n", dirname);
 	char **dirs = (char **) calloc(mhdd.cdirs+1, sizeof(char *));
 
+	struct stat st;
+
 	typedef struct dir_item {
 		char            *name;
 		struct stat     *st;
-		UT_hash_handle   hh;
 	} dir_item;
 
-	dir_item * items_ht = NULL;
-
-
-	struct stat st;
 
 	// find all dirs
 	for(i = j = found = 0; i<mhdd.cdirs; i++) {
@@ -194,6 +212,8 @@
 		return -errno;
 	}
 
+	GHashTable* hash = g_hash_table_new(g_str_hash, g_str_equal);
+
 	// read directories
 	for (i = 0; dirs[i]; i++) {
 		struct dirent *de;
@@ -204,51 +224,43 @@
 		while((de = readdir(dh))) {
 			// find dups
 			
-			struct dir_item *prev;
-
-			HASH_FIND_STR(items_ht, de->d_name, prev);
-
-			if (prev) {
+			if(g_hash_table_lookup(hash, de->d_name))
+			{
 				continue;
 			}
 
 			// add item
 			char *object_name = create_path(dirs[i], de->d_name);
-			struct dir_item *new_item =
-				calloc(1, sizeof(struct dir_item));
+			struct dir_item *new_item =	calloc(1, sizeof(struct dir_item));
 
 			new_item->name = strdup(de->d_name);
 			new_item->st = calloc(1, sizeof(struct stat));
 			lstat(object_name, new_item->st);
 
-			HASH_ADD_KEYPTR(
-				hh,
-				items_ht,
-				new_item->name,
-				strlen(new_item->name),
-				new_item
-			);
+			g_hash_table_insert(hash, new_item->name, new_item);
 			free(object_name);
 		}
 
 		closedir(dh);
 	}
 
-	dir_item *item, *tmp;
-
-	// fill list
-	HASH_ITER(hh, items_ht, item, tmp) {
-		if (filler(buf, item->name, item->st, 0))
-			break;
-	}
+	dir_item *item;
 
-	// free memory
-	HASH_ITER(hh, items_ht, item, tmp) {
+	gpointer key, value;	
+	GHashTableIter iter;
+	g_hash_table_iter_init(&iter, hash);
+
+	while(g_hash_table_iter_next (&iter, &key, &value))
+	{
+		item = (dir_item*) value;
+		int result = filler(buf, item->name, item->st, 0);
 		free(item->name);
 		free(item->st);
 		free(item);
+		if(result) break;
 	}
-	HASH_CLEAR(hh, items_ht);
+
+	g_hash_table_destroy(hash);
 
 	for (i = 0; dirs[i]; i++)
 		free(dirs[i]);
@@ -1008,6 +1020,19 @@
 }
 #endif
 
+static void limits_init()
+{
+   struct rlimit limit;
+   limit.rlim_cur = 512000;
+   limit.rlim_max = 512000;
+
+   if(setrlimit(RLIMIT_NOFILE, &limit) != 0)
+   {
+      perror("setrlimit() failed");
+      exit(-1);
+   }
+}
+
 // functions links
 static struct fuse_operations mhdd_oper = {
 	.getattr    	= mhdd_stat,
@@ -1048,5 +1073,7 @@
 	mhdd_debug_init();
 	struct fuse_args *args = parse_options(argc, argv);
 	flist_init();
+	limits_init();
+	signal(SIGSEGV, save_backtrace);
 	return fuse_main(args->argc, args->argv, &mhdd_oper, 0);
 }
--- a/src/usage.c	2012-06-17 16:09:56.000000000 +0200
+++ b/src/usage.c	2015-12-21 16:32:29.000000000 +0100
@@ -25,6 +25,7 @@
 		"\n"
 		"Multi-hdd FUSE filesystem\n"
 		" Copyright (C) 2008, Dmitry E. Oboukhov <dimka@avanto.org>\n"
+		" Copyright (C) 2015, Valentin Dudouyt <valentin.dudouyt@gmail.com>\n"		
 		"\n"
 		"Usage:\n"
 		" mhddfs dir1,dir2.. mountpoint [ -o OPTIONS ]\n"
--- a/Makefile	2016-01-05 16:45:10.184105001 +0100
+++ b/Makefile	2015-12-21 16:32:29.000000000 +0100
@@ -53,7 +53,7 @@
 ifeq ($(DEBVERSION), $(VERSION))
 all: $(TARGET)
 else
-all: update_version $(TARGET)
+all: $(TARGET)
 endif
 
 update_version: