added pack statements for gcc

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@132

include/dos_inc.h

@@ -24,7 +24,7 @@
 
 #if defined (_MSC_VER)
 #pragma pack(1)
-#endif#
+#endif
 struct CommandTail{
   Bit8u count;				/* number of bytes returned */
   char buffer[127];			 /* the buffer itself */

include/dos_system.h

@@ -35,7 +35,9 @@ enum {
 	DOS_ATTR_ARCHIVE=	0x20
 };
 
-#pragma pack (1)
+#if defined (_MSC_VER)
+#pragma pack(1)
+#endif
 struct DTA_FindBlock {
 	Bit8u sdrive;								/* The Drive the search is taking place */
 	Bit16u sattr;								/* The attributes that need to be found */
@@ -45,8 +47,13 @@ struct DTA_FindBlock {
 	Bit16u date;
 	Bit32u size;
 	char name[DOS_NAMELENGTH];
-};
-#pragma pack ()
+}
+#if defined (_MSC_VER)
+;
+#pragma pack()
+#else
+__attribute__ ((packed));
+#endif
 
 class DOS_File {
 public:

src/dos/dos_execute.cpp

@@ -21,8 +21,9 @@
 #include "mem.h"
 #include "dos_inc.h"
 #include "cpu.h"
+#if defined (_MSC_VER)
 #pragma pack(1)
-
+#endif
 
 struct EXE_Header {
 	
@@ -40,8 +41,13 @@ struct EXE_Header {
 	Bit16u initCS;
 	Bit16u reloctable;
 	Bit16u overlay;
-};
+}
+#if defined (_MSC_VER)
+;
 #pragma pack()
+#else
+__attribute__ ((packed));
+#endif
 
 #define MAGIC1 0x5a4d
 #define MAGIC2 0x4d5a

src/dos/dos_tables.cpp

@@ -20,13 +20,19 @@
 #include "mem.h"
 #include "dos_inc.h"
 
+#if defined (_MSC_VER)
 #pragma pack(1)
-
+#endif
 struct DOS_TableCase {	
 	Bit16u size;
 	Bit8u chars[256];
-};
+}
+#if defined (_MSC_VER)
+;
 #pragma pack()
+#else
+__attribute__ ((packed));
+#endif
 
 
 RealPt DOS_TableUpCase;

src/ints/int10_misc.cpp

@@ -23,7 +23,9 @@
 
 
 
+#if defined (_MSC_VER)
 #pragma pack(1)
+#endif
 struct Dynamic_Functionality {
 	RealPt static_table;		/* 00h   DWORD  address of static functionality table */
 	Bit8u cur_mode;				/* 04h   BYTE   video mode in effect */
@@ -68,9 +70,13 @@ struct Dynamic_Functionality {
 									7 reserved
 								*/
 	Bit8u reserved2[13];		/*  33h 13 BYTEs reserved (00h) */
-};
+}
+#if defined (_MSC_VER)
+;
 #pragma pack()
-
+#else
+__attribute__ ((packed));
+#endif