Lucho reported that MSC compiled kernels now work after all. Let's mark

those nasty "BSS" variables explicitly then to try to avoid future problems.


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@880 6ac86273-5f31-0410-b378-82cca8765d1b

docs/build.txt

@@ -31,8 +31,8 @@ enable it.
 
 This kernel compiles with Turbo C 2.01, Turbo C++ 1.01 (now freely
 available!), Turbo C 3.0, Borland C 4.51 & 5.01.  It should work with
-other Borland compilers and (Open)Watcom C. Microsoft C and GCC can
-compile the kernel but the result does *not* work.
+other Borland and Microsoft compilers and (Open)Watcom C. GCC can
+compile the kernel but the result does *not* work (no 16-bit x86 support).
 
 The OpenWatcom 1.0 compiler (or later) for DOS can be downloaded at
 www.openwatcom.org: you need at least the following zips from

kernel/config.c

@@ -58,9 +58,9 @@ struct MenuSelector
 };
 
 /** Structure below holds the menu-strings */
-STATIC struct MenuSelector MenuStruct[MENULINESMAX];
+STATIC struct MenuSelector MenuStruct[MENULINESMAX] BSS_INIT({0});
 
-int nMenuLine;
+int nMenuLine BSS_INIT(0);
 BOOL MenuColor = -1;
 
 STATIC void WriteMenuLine(int MenuSelected)
@@ -116,13 +116,13 @@ STATIC void SelectLine(int MenuSelected)
   WriteMenuLine(MenuSelected);
 }
 
-UWORD umb_start, UMB_top;
-UWORD ram_top; /* How much ram in Kbytes               */
-size_t ebda_size;
+UWORD umb_start BSS_INIT(0), UMB_top BSS_INIT(0);
+UWORD ram_top BSS_INIT(0); /* How much ram in Kbytes               */
+size_t ebda_size BSS_INIT(0);
 
-static UBYTE ErrorAlreadyPrinted[128];
+static UBYTE ErrorAlreadyPrinted[128] BSS_INIT({0});
 
-char master_env[128];
+char master_env[128] BSS_INIT({0});
 static char *envp = master_env;
 
 struct config Config = {
@@ -148,23 +148,23 @@ struct config Config = {
       , 0xFFFF                  /* default value for switches=/E:nnnn */
 };
 
-STATIC seg base_seg;
-STATIC seg umb_base_seg;
-BYTE FAR *lpTop;
-STATIC unsigned nCfgLine;
-COUNT UmbState;
-STATIC BYTE szLine[256];
-STATIC BYTE szBuf[256];
+STATIC seg base_seg BSS_INIT(0);
+STATIC seg umb_base_seg BSS_INIT(0);
+BYTE FAR *lpTop BSS_INIT(0);
+STATIC unsigned nCfgLine BSS_INIT(0);
+COUNT UmbState BSS_INIT(0);
+STATIC BYTE szLine[256] BSS_INIT({0});
+STATIC BYTE szBuf[256] BSS_INIT({0});
 
-BYTE singleStep;        /* F8 processing */
-BYTE SkipAllConfig;     /* F5 processing */
-BYTE askThisSingleCommand;      /* ?device=  device?= */
-BYTE DontAskThisSingleCommand;  /* !files=            */
+BYTE singleStep BSS_INIT(FALSE);        /* F8 processing */
+BYTE SkipAllConfig BSS_INIT(FALSE);     /* F5 processing */
+BYTE askThisSingleCommand BSS_INIT(FALSE);      /* ?device=  device?= */
+BYTE DontAskThisSingleCommand BSS_INIT(FALSE);  /* !files=            */
 
 COUNT MenuTimeout = -1;
-BYTE  MenuSelected;
-UCOUNT MenuLine;
-UCOUNT Menus;
+BYTE  MenuSelected BSS_INIT(0);
+UCOUNT MenuLine BSS_INIT(0);
+UCOUNT Menus BSS_INIT(0);
 
 STATIC VOID CfgMenuColor(BYTE * pLine);
 
@@ -313,9 +313,9 @@ int  findend(BYTE * s)
   return nLen;
 }
 
-BYTE *pLineStart;
+BYTE *pLineStart BSS_INIT(0);
 
-BYTE HMAState;
+BYTE HMAState BSS_INIT(0);
 #define HMA_NONE 0              /* do nothing */
 #define HMA_REQ 1               /* DOS = HIGH detected */
 #define HMA_DONE 2              /* Moved kernel to HMA */
@@ -1634,7 +1634,7 @@ STATIC VOID mcb_init_copy(UCOUNT seg, UWORD size, mcb *near_mcb)
 
 STATIC VOID mcb_init(UCOUNT seg, UWORD size, BYTE type)
 {
-  static mcb near_mcb;
+  static mcb near_mcb BSS_INIT({0});
   near_mcb.m_type = type;
   mcb_init_copy(seg, size, &near_mcb);
 }

kernel/init-mod.h

@@ -25,6 +25,20 @@
 #include "init-dat.h"
 
 #include "kconfig.h"
+
+/* MSC places uninitialized data into COMDEF records,
+   that end up in DATA segment. this can't be tolerated in INIT code.
+   please make sure, that ALL data in INIT is initialized !!
+
+   These guys are marked BSS_INIT to mark that they really should be BSS
+   but can't be because of MS
+*/
+#ifdef _MSC_VER
+#define BSS_INIT(x) = x
+#else
+#define BSS_INIT(x)
+#endif
+
 extern struct _KernelConfig InitKernelConfig;
 
 /*

kernel/initdisk.c

@@ -32,8 +32,8 @@ static BYTE *dskRcsId =
     "$Id$";
 #endif
 
-UBYTE InitDiskTransferBuffer[SEC_SIZE];
-COUNT nUnits;
+UBYTE InitDiskTransferBuffer[SEC_SIZE] BSS_INIT({0});
+COUNT nUnits BSS_INIT(0);
 
 /*
  *    Rev 1.0   13 May 2001  tom ehlert

kernel/inithma.c

@@ -71,9 +71,9 @@ static BYTE *RcsId =
     "$Id$";
 #endif
 
-BYTE DosLoadedInHMA = FALSE;    /* set to TRUE if loaded HIGH          */
-BYTE HMAclaimed = FALSE;        /* set to TRUE if claimed from HIMEM   */
-UWORD HMAFree = 0;              	/* first byte in HMA not yet used      */
+BYTE DosLoadedInHMA BSS_INIT(FALSE);  /* set to TRUE if loaded HIGH          */
+BYTE HMAclaimed BSS_INIT(0);          /* set to TRUE if claimed from HIMEM   */
+UWORD HMAFree BSS_INIT(0);            /* first byte in HMA not yet used      */
 
 STATIC void InstallVDISK(void);
 

kernel/main.c

@@ -43,7 +43,7 @@ static char copyright[] =
     "GNU General Public License as published by the Free Software Foundation;\n"
     "either version 2, or (at your option) any later version.\n";
 
-struct _KernelConfig InitKernelConfig;
+struct _KernelConfig InitKernelConfig BSS_INIT({0});
 
 STATIC VOID InitIO(void);
 
@@ -64,12 +64,10 @@ __segment DosDataSeg = 0;       /* serves for all references to the DOS DATA seg
                                  */
 __segment DosTextSeg = 0;
 
-struct lol FAR *LoL;
-
-#else
-struct lol FAR *LoL = &DATASTART;
 #endif
 
+struct lol FAR *LoL = &DATASTART;
+
 VOID ASMCFUNC FreeDOSmain(void)
 {
   unsigned char drv;
@@ -79,7 +77,6 @@ VOID ASMCFUNC FreeDOSmain(void)
   extern FAR prn_dev;
   DosDataSeg = (__segment) & DATASTART;
   DosTextSeg = (__segment) & prn_dev;
-  LoL = &DATASTART;
 #endif
 
                         /*  if the kernel has been UPX'ed,