diff --git a/common.c b/common.c
index e39febd1e..d1d2fe21a 100644
--- a/common.c
+++ b/common.c
@@ -212,8 +212,13 @@ wchar_t *str2wcs( const char *in )
 	size_t len = strlen(in);
 	
 	out = malloc( sizeof(wchar_t)*(len+1) );
+
+	if( !out )
+	{
+		die_mem();
+	}
+
 	return str2wcs_internal( in, out );
-	
 }
 
 wchar_t *str2wcs_internal( const char *in, wchar_t *out )
@@ -226,11 +231,6 @@ wchar_t *str2wcs_internal( const char *in, wchar_t *out )
 	
 	memset( &state, 0, sizeof(state) );
 	
-	if( !out )
-	{
-		die_mem();
-	}
-
 	while( in[in_pos] )
 	{
 		res = mbrtowc( &out[out_pos], &in[in_pos], len-in_pos, &state );
diff --git a/complete.c b/complete.c
index 1e9321517..d3de7dd06 100644
--- a/complete.c
+++ b/complete.c
@@ -481,8 +481,10 @@ void complete_remove( const wchar_t *cmd,
 							{
 								wchar_t *pos2 = pos+1;
 								while( *pos2 == L':' )
+								{
 									pos2++;
-
+								}
+								
 								memmove( pos,
 										 pos2,
 										 sizeof(wchar_t)*wcslen(pos2) );
@@ -500,7 +502,9 @@ void complete_remove( const wchar_t *cmd,
 						free( o );
 					}
 					else
+					{
 						oprev = o;
+					}
 				}
 			}
 
@@ -523,7 +527,9 @@ void complete_remove( const wchar_t *cmd,
 		}
 
 		if( e )
+		{
 			eprev = e;
+		}
 	}
 }
 
@@ -541,8 +547,14 @@ static void parse_cmd_string( const wchar_t *str,
 	/* Get the path of the command */
 	path = get_filename( str );
 	if( path == 0 )
+	{
+		/**
+		   Use the empty string as the 'path' for commands that can
+		   not be found.
+		*/
 		path = wcsdup(L"");
-
+	}
+	
 	/* Make sure the path is not included in the command */
 	cmd = wcsrchr( str, L'/' );
 	if( cmd != 0 )
@@ -611,11 +623,11 @@ int complete_is_valid_option( const wchar_t *str,
 		return 0;
 	}
 
-
-
 	if( !(short_validated = malloc( wcslen( opt ) )))
+	{
 		die_mem();
-
+	}
+	
 	memset( short_validated, 0, wcslen( opt ) );
 
 	hash_init( &gnu_match_hash,
@@ -649,8 +661,10 @@ int complete_is_valid_option( const wchar_t *str,
 		const wchar_t *a;
 
 		if( !wildcard_match( match, i->cmd ) )
+		{
 			continue;
-
+		}
+		
 		found_match = 1;
 
 		if( !i->authorative )
@@ -666,15 +680,19 @@ int complete_is_valid_option( const wchar_t *str,
 			for( o = i->first_option; o; o=o->next )
 			{
 				if( o->old_mode )
+				{
 					continue;
-
+				}
+				
 				if( wcsncmp( &opt[2], o->long_opt, gnu_opt_len )==0)
 				{
 					hash_put( &gnu_match_hash, o->long_opt, L"" );
 					if( (wcsncmp( &opt[2],
 								  o->long_opt,
 								  wcslen( o->long_opt) )==0) )
+					{
 						is_gnu_exact=1;
+					}
 				}
 			}
 		}
@@ -926,24 +944,30 @@ const wchar_t *complete_get_desc( const wchar_t *filename )
 				switch( errno )
 				{
 					case ENOENT:
+					{
 						sb_printf( get_desc_buff, L"%lc%ls", COMPLETE_SEP, COMPLETE_ROTTEN_SYMLINK_DESC );
 						break;
-
+					}
+					
 					case EACCES:
+					{
 						break;
-
+					}
+					
 					default:
+					{
 						if( errno == ELOOP )
 						{
 							sb_printf( get_desc_buff, L"%lc%ls", COMPLETE_SEP, COMPLETE_LOOP_SYMLINK_DESC );
 						}
 
 						/*
-						  Some kind of broken symlink. We ignore it
-						  here, and it will get a 'file' description,
-						  or one based on suffix.
+						  Some kind of unknown broken symlink. We
+						  ignore it here, and it will get a 'file'
+						  description, or one based on suffix.
 						*/
 						break;
+					}
 				}
 			}
 
@@ -1013,19 +1037,14 @@ static void copy_strings_with_prefix( array_list_t *comp_out,
 	if(!tmp)
 		return;
 
-	if( tmp[0] == L'~' )
-	{
-		tmp=expand_tilde(wc);
-	}
-	
 	wc = parse_util_unescape_wildcards( tmp );
 	free(tmp);
 	
 	for( i=0; i<al_get_count( possible_comp ); i++ )
 	{
 		wchar_t *next_str = (wchar_t *)al_get( possible_comp, i );
-
-		wildcard_complete( next_str, wc, desc, desc_func, comp_out );
+		if( next_str )
+			wildcard_complete( next_str, wc, desc, desc_func, comp_out );
 	}
 
 	free( wc );
@@ -1358,10 +1377,26 @@ static void complete_from_args( const wchar_t *str,
 	for( i=0; i< al_get_count( &possible_comp ); i++ )
 	{
 		wchar_t *next = (wchar_t *)al_get( &possible_comp, i );
-		al_set( &possible_comp , i, unescape( next, 0 ) );
-		free( next );
+		wchar_t *next_unescaped;
+		if( next )
+		{
+			next_unescaped = unescape( next, 0 );
+			if( next_unescaped )
+			{
+				al_set( &possible_comp , i, next_unescaped );
+			}
+			else
+			{
+				debug( 2, L"Could not expand string %ls on line %d of file %s", next, __LINE__, __FILE__ );
+			}
+			free( next );
+		}
+		else
+		{
+			debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+		}
 	}
-
+	
 	copy_strings_with_prefix( comp_out, str, desc, 0, &possible_comp );
 
 	al_foreach( &possible_comp, (void (*)(const void *))&free );
@@ -1674,11 +1709,11 @@ static void complete_param_expand( wchar_t *str,
 		comp_str = str;
 	}
 	
-	debug( 2,
+	debug( 3,
 		   L"expand_string( \"%ls\", comp_out, EXPAND_SKIP_SUBSHELL | ACCEPT_INCOMPLETE | %ls );",
 		   comp_str,
 		   do_file?L"0":L"EXPAND_SKIP_WILDCARDS" );
-
+	
 	expand_string( 0, 
 				   wcsdup(comp_str),
 				   comp_out,
@@ -1753,10 +1788,8 @@ static int try_complete_variable( const wchar_t *cmd,
 		{
 			return 0;
 		}
-
 	}
 	return 0;
-
 }
 
 /**
diff --git a/env_universal.c b/env_universal.c
index 5344ad733..ab817e4d2 100644
--- a/env_universal.c
+++ b/env_universal.c
@@ -214,7 +214,7 @@ void env_universal_init( wchar_t * p,
 						 void (*sf)(),
 						 void (*cb)( int type, const wchar_t *name, const wchar_t *val ))
 {
-	debug( 2, L"env_universal_init()" );
+	debug( 3, L"env_universal_init()" );
 	path=p;
 	user=u;
 	start_fishd=sf;	
@@ -233,7 +233,7 @@ void env_universal_init( wchar_t * p,
 	{
 		env_universal_barrier();
 	}
-	debug( 2, L"end env_universal_init()" );
+	debug( 3, L"end env_universal_init()" );
 }
 
 void env_universal_destroy()
diff --git a/env_universal_common.c b/env_universal_common.c
index e028759b8..07123e0ca 100644
--- a/env_universal_common.c
+++ b/env_universal_common.c
@@ -105,7 +105,7 @@ static int get_names_show_unexported;
 
 void env_universal_common_init( void (*cb)(int type, const wchar_t *key, const wchar_t *val ) )
 {
-	debug( 2, L"Init env_universal_common" );
+	debug( 3, L"Init env_universal_common" );
 	callback = cb;
 	hash_init( &env_universal_var, &hash_wcs_func, &hash_wcs_cmp );
 }
@@ -229,7 +229,7 @@ static int match( const wchar_t *msg, const wchar_t *cmd )
 static void parse_message( wchar_t *msg, 
 						   connection_t *src )
 {
-	debug( 2, L"parse_message( %ls );", msg );
+	debug( 3, L"parse_message( %ls );", msg );
 	
 	if( msg[0] == L'#' )
 		return;
diff --git a/exec.c b/exec.c
index 7738877d7..627fec476 100644
--- a/exec.c
+++ b/exec.c
@@ -1260,10 +1260,16 @@ int exec_subshell( const wchar_t *cmd,
 					{
 						wchar_t *el = str2wcs( begin );
 						if( el )
+						{
 							al_push( l, el );
+						}
+						else
+						{
+							debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+						}
 					}				
 					io_buffer_destroy( io_buffer );
-				
+					
 					return status;
 				
 				case '\n':
@@ -1271,7 +1277,14 @@ int exec_subshell( const wchar_t *cmd,
 					wchar_t *el;
 					*end=0;
 					el = str2wcs( begin );
-					al_push( l, el );
+					if( el )
+					{
+						al_push( l, el );
+					}
+					else
+					{
+						debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+					}
 					begin = end+1;
 					break;
 				}
diff --git a/expand.c b/expand.c
index af7d34345..4664a8b4c 100644
--- a/expand.c
+++ b/expand.c
@@ -1189,6 +1189,18 @@ static int expand_subshell( wchar_t *in, array_list_t *out )
 	int i, j;
 	const wchar_t *item_begin;
 
+	if( !in )
+	{
+		debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+		return 0;		
+	}
+
+	if( !out )
+	{
+		debug( 2, L"Got null pointer on line %d of file %s", __LINE__, __FILE__ );
+		return 0;		
+	}
+
 	switch( parse_util_locate_cmdsubst(in,
 									   &paran_begin,
 									   &paran_end,
@@ -1205,7 +1217,6 @@ static int expand_subshell( wchar_t *in, array_list_t *out )
 		case 1:
 
 			break;
-
 	}
 
 	len1 = (paran_begin-in);
@@ -1254,10 +1265,10 @@ static int expand_subshell( wchar_t *in, array_list_t *out )
             sb_append_substring( &whole_item, sub_item2, item_len );
 			sb_append_char( &whole_item, INTERNAL_SEPARATOR );
             sb_append( &whole_item, tail_item );
-
-            al_push( out, whole_item.buff );
+			
+			al_push( out, whole_item.buff );
         }
-
+		
         free( sub_item2 );
     }
 	free(in);
@@ -1438,23 +1449,18 @@ int expand_string( void *context,
 
 	if( EXPAND_SKIP_SUBSHELL & flags )
 	{
-		wchar_t *pos = str;
-
-		while( 1 )
+		const wchar_t *begin, *end;
+		
+		if( parse_util_locate_cmdsubst( str,
+										&begin,
+										&end,
+										1 ) != 0 )
 		{
-			pos = wcschr( pos, L'(' );
-			if( pos == 0 )
-				break;
-
-			if( (pos == str) || ( *(pos-1) != L'\\' ) )
-			{
-				error( SUBSHELL_ERROR, -1, L"Subshells not allowed" );
-				free( str );
-				al_destroy( &list1 );
-				al_destroy( &list2 );
-				return EXPAND_ERROR;
-			}
-			pos++;
+			error( SUBSHELL_ERROR, -1, L"Subshells not allowed" );
+			free( str );
+			al_destroy( &list1 );
+			al_destroy( &list2 );
+			return EXPAND_ERROR;
 		}
 		al_push( &list1, str );
 	}
@@ -1483,7 +1489,10 @@ int expand_string( void *context,
 			free( (void *)al_get( in, i ) );
 
 			if( !next )
-				continue;
+			{
+				debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+				continue;				
+			}
 
 			if( EXPAND_SKIP_VARIABLES & flags )
 			{
@@ -1492,7 +1501,6 @@ int expand_string( void *context,
 					if( *tmp == VARIABLE_EXPAND )
 						*tmp = L'$';
 				al_push( out, next );
-
 			}
 			else
 			{
@@ -1513,6 +1521,13 @@ int expand_string( void *context,
 		for( i=0; i<al_get_count( in ); i++ )
 		{
 			wchar_t *next = (wchar_t *)al_get( in, i );
+
+			if( !next )
+			{
+				debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+				continue;				
+			}	
+
 			if( !expand_brackets( next, flags, out ))
 			{
 				al_destroy( in );
@@ -1528,6 +1543,13 @@ int expand_string( void *context,
 		for( i=0; i<al_get_count( in ); i++ )
 		{
 			wchar_t *next = (wchar_t *)al_get( in, i );
+
+			if( !next )
+			{
+				debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+				continue;				
+			}	
+
 			if( !(next=expand_tilde_internal( next ) ) )
 			{
 				al_destroy( in );
@@ -1572,6 +1594,12 @@ int expand_string( void *context,
 			wchar_t *next = (wchar_t *)al_get( in, i );
 			int wc_res;
 
+			if( !next )
+			{
+				debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+				continue;				
+			}	
+
 			remove_internal_separator( next, EXPAND_SKIP_WILDCARDS & flags );
 			
 			if( ((flags & ACCEPT_INCOMPLETE) && (!(flags & EXPAND_SKIP_WILDCARDS))) ||
@@ -1590,27 +1618,46 @@ int expand_string( void *context,
 				switch( wc_res )
 				{
 					case 0:
+					{
 						if( !(flags & ACCEPT_INCOMPLETE) )
 						{
 							if( res == EXPAND_OK )
 								res = EXPAND_WILDCARD_NO_MATCH;
 							break;
 						}
-
+					}
+					
 					case 1:
+					{
+						int j;
 						res = EXPAND_WILDCARD_MATCH;
 						sort_list( out );
-						al_push_all( end_out, out );
+
+						for( j=0; j<al_get_count( out ); j++ )
+						{
+							wchar_t *next = (wchar_t *)al_get( out, j );
+							if( !next )
+							{
+								debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+								continue;				
+							}	
+							al_push( end_out, next );
+						}
 						al_truncate( out, 0 );
 						break;
+					}
 				}
 			}
 			else
 			{
 				if( flags & ACCEPT_INCOMPLETE)
+				{
 					free( next );
+				}
 				else
+				{
 					al_push( end_out, next );
+				}
 			}
 		}
 		al_destroy( in );
diff --git a/main.c b/main.c
index 25875958a..d65fc9ed7 100644
--- a/main.c
+++ b/main.c
@@ -122,6 +122,10 @@ int main( int argc, char **argv )
 					"command", required_argument, 0, 'c' 
 				}
 				,
+				{
+					"debug-level", required_argument, 0, 'd' 
+				}
+				,
 				{
 					"interactive", no_argument, 0, 'i' 
 				}
@@ -152,14 +156,14 @@ int main( int argc, char **argv )
 		
 		int opt = getopt_long( argc,
 							   argv, 
-							   "hilvc:p:", 
+							   "hilvc:p:d:", 
 							   long_options, 
 							   &opt_index );
 		
 #else	
 		int opt = getopt( argc,
 						  argv, 
-						  "hilvc:p:" );
+						  "hilvc:p:d:" );
 #endif
 		if( opt == -1 )
 			break;
@@ -174,6 +178,22 @@ int main( int argc, char **argv )
 				is_interactive_session = 0;
 				break;
 
+			case 'd':		
+			{
+				char *end;
+				int tmp = strtol(optarg, &end, 10);
+				if( tmp >= 0 && tmp <=10 && !*end )
+				{
+					debug_level=tmp;
+				}
+				else
+				{
+					debug( 0, _(L"Invalid value '%s' for debug level switch"), optarg );
+					exit(1);
+				}
+				break;
+			}
+			
 			case 'h':
 				cmd = "help";
 				break;
@@ -233,7 +253,7 @@ int main( int argc, char **argv )
 			wchar_t *cmd_wcs = str2wcs( cmd );
 			res = eval( cmd_wcs, 0, TOP );
 			free(cmd_wcs);
-			reader_exit(0);			
+			reader_exit(0);
 		}
 		else
 		{
diff --git a/parse_util.c b/parse_util.c
index 57f36b027..18ffad8a2 100644
--- a/parse_util.c
+++ b/parse_util.c
@@ -155,16 +155,12 @@ int parse_util_locate_cmdsubst( const wchar_t *in,
 		return 0;
 	}
 
-	*begin = paran_begin;
-	*end = paran_count?in+wcslen(in):paran_end;
+	if( begin )
+		*begin = paran_begin;
+	if( end )
+		*end = paran_count?in+wcslen(in):paran_end;
 	
-/*	assert( *begin >= in );
-	assert( *begin < (in+wcslen(in) ) );
-	assert( *end >= *begin );
-	assert( *end < (in+wcslen(in) ) );
-*/
 	return 1;
-
 }
 
 
diff --git a/parser.c b/parser.c
index bf339e778..c6b0b8d36 100644
--- a/parser.c
+++ b/parser.c
@@ -708,7 +708,7 @@ wchar_t *get_filename( const wchar_t *cmd )
 {
 	wchar_t *path;
 
-	debug( 2, L"get_filename( '%ls' )", cmd );
+	debug( 3, L"get_filename( '%ls' )", cmd );
 
 	if(wcschr( cmd, L'/' ) != 0 )
 	{
@@ -948,7 +948,14 @@ int eval_args( const wchar_t *line, array_list_t *args )
 		{
 			case TOK_STRING:
 			{
-				if( expand_string( 0, wcsdup(tok_last( &tok )), args, 0 ) == EXPAND_ERROR )
+				wchar_t *tmp = wcsdup(tok_last( &tok ));
+				
+				if( !tmp )
+				{
+					die_mem();
+				}
+				
+				if( expand_string( 0, tmp, args, 0 ) == EXPAND_ERROR )
 				{
 					err_pos=tok_get_pos( &tok );
 					do_loop=0;
diff --git a/reader.c b/reader.c
index f1301277f..8e87b5d61 100644
--- a/reader.c
+++ b/reader.c
@@ -567,11 +567,12 @@ static void remove_duplicates( array_list_t *l )
 
 	prev = (wchar_t *)al_get( l, 0 );
 	for( in=1, out=1; in < al_get_count( l ); in++ )
-	{
+	{		
 		wchar_t *curr = (wchar_t *)al_get( l, in );
+
 		if( fldcmp( prev, curr )==0 )
 		{
-			free( curr );
+			free( curr );			
 		}
 		else
 		{
@@ -2036,7 +2037,6 @@ void reader_set_buffer( wchar_t *b, int p )
 	else
 	{
 		data->buff_pos=l;
-//		fwprintf( stderr, L"Pos %d\n", l );
 	}
 
 	reader_super_highlight_me_plenty( data->buff,
diff --git a/wildcard.c b/wildcard.c
index fae759708..7c31f6a1f 100644
--- a/wildcard.c
+++ b/wildcard.c
@@ -151,13 +151,32 @@ static int wildcard_complete_internal( const wchar_t *orig,
 									   const wchar_t *(*desc_func)(const wchar_t *),
 									   array_list_t *out )
 {
+	if( !wc )
+	{
+		debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+		return 0;		
+	}
+	
+	if( !str )
+	{
+		debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+		return 0;		
+	}
+	
+	if( !orig )
+	{
+		debug( 2, L"Got null string on line %d of file %s", __LINE__, __FILE__ );
+		return 0;		
+	}
+
 	if( *wc == 0 &&
 		( ( *str != L'.') || (!is_first)) )
 	{
-		if( !out )
-			return 1;
-		
 		wchar_t *new;
+		if( !out )
+		{
+			return 1;
+		}
 			
 		if( wcschr( str, PROG_COMPLETE_SEP ) )
 		{
@@ -165,7 +184,7 @@ static int wildcard_complete_internal( const wchar_t *orig,
 			  This completion has an embedded description, du not use the generic description
 			*/
 			wchar_t *sep;
-				
+			
 			new = wcsdup( str );
 			sep = wcschr(new, PROG_COMPLETE_SEP );
 			*sep = COMPLETE_SEP;			
@@ -661,15 +680,19 @@ int wildcard_expand( const wchar_t *wc,
 								if( wc_end )
 								{
 									new_wc=wc_end+1;
+									/*
+									  Accept multiple '/' as a single direcotry separator
+									*/
 									while(*new_wc==L'/')
+									{
 										new_wc++;
+									}
 								}
 								
 								res |= wildcard_expand( new_wc,
 														new_dir, 
 														flags, 
 														out );
-
 							}
 							
 							/*
@@ -694,8 +717,10 @@ int wildcard_expand( const wchar_t *wc,
 	closedir( dir );
 	
 	if( flags & ACCEPT_INCOMPLETE )
+	{
 		sb_destroy( &sb_desc );
-	
+	}
+
 	return res;
 }