Addresses issue #185 - all optimisations off by default

[rmac] / object.c

diff --git a/object.c b/object.c
index 7545866fd8a9f10106aad0adf726715fb0f951d4..ada5337010c9f371de680c26ef317b6308654a82 100644 (file)
--- a/object.c
+++ b/object.c
@@ -1,7 +1,7 @@
 //
-// RMAC - Reboot's Macro Assembler for all Atari computers
+// RMAC - Renamed Macro Assembler for all Atari computers
 // OBJECT.C - Writing Object Files
-// Copyright (C) 199x Landon Dyer, 2011-2020 Reboot and Friends
+// Copyright (C) 199x Landon Dyer, 2011-2021 Reboot and Friends
 // RMAC derived from MADMAC v1.07 Written by Landon Dyer, 1986
 // Source utilised with the kind permission of Landon Dyer
 //
@@ -161,6 +161,24 @@ uint8_t * AddSymEntry(register uint8_t * buf, SYM * sym, int globflag)
 //
 // Add an entry to the BSD symbol table
 //
+// From stab.def (https://sites.uclouvain.be/SystInfo/usr/include/bits/stab.def.html):
+/*
+_________________________________________________
+| 00 - 1F are not dbx stab symbols              |
+| In most cases, the low bit is the EXTernal bit|
+
+| 00 UNDEF  | 02 ABS    | 04 TEXT   | 06 DATA   |
+| 01  |EXT  | 03  |EXT  | 05  |EXT  | 07  |EXT  |
+
+| 08 BSS    | 0A INDR   | 0C FN_SEQ | 0E WEAKA  |
+| 09  |EXT  | 0B        | 0D WEAKU  | 0F WEAKT  |
+
+| 10 WEAKD  | 12 COMM   | 14 SETA   | 16 SETT   |
+| 11 WEAKB  | 13        | 15        | 17        |
+
+| 18 SETD   | 1A SETB   | 1C SETV   | 1E WARNING|
+| 19        | 1B        | 1D        | 1F FN     |
+*/
 uint8_t * AddBSDSymEntry(uint8_t * buf, SYM * sym, int globflag)
 {
        chptr = buf;                                            // Point to buffer for depositing longs
@@ -173,14 +191,16 @@ uint8_t * AddBSDSymEntry(uint8_t * buf, SYM * sym, int globflag)
        {
                z = 0x02000000;                                 // Set equated flag
        }
-       else
+
+       // If a symbol is both EQUd and flagged as TBD then we let
+       // the later take precedence. Otherwise the linker will not even
+       // bother trying to relocate the address during link time
+
+       switch (w1 & TDB)
        {
-               switch (w1 & TDB)
-               {
-               case TEXT: z = 0x04000000; break;       // Set TEXT segment flag
-               case DATA: z = 0x06000000; break;       // Set DATA segment flag
-               case BSS : z = 0x08000000; break;       // Set BSS segment flag
-               }
+       case TEXT: z = 0x04000000; break;       // Set TEXT segment flag
+       case DATA: z = 0x06000000; break;       // Set DATA segment flag
+       case BSS : z = 0x08000000; break;       // Set BSS segment flag
        }
 
        if (globflag)
@@ -222,7 +242,7 @@ uint8_t * AddELFSymEntry(uint8_t * buf, SYM * sym, int globflag)
        if (w1 & DEFINED)
        {
                if (globflag)           // Export the symbol
-                       st_info |= 16;   //STB_GLOBAL (1<<4)
+                       st_info |= 16;  // STB_GLOBAL (1<<4)
        }
        else if (w1 & (GLOBAL | REFERENCED))
                st_info |= 16;
@@ -230,7 +250,7 @@ uint8_t * AddELFSymEntry(uint8_t * buf, SYM * sym, int globflag)
        D_byte(st_info);
        D_byte(0);                              // st_other
 
-       uint16_t st_shndx = 0xFFF1;     // Assume absolute (equated) number
+       uint16_t st_shndx = SHN_ABS;    // Assume absolute (equated) number
 
        if (w1 & TEXT)
                st_shndx = elfHdrNum[ES_TEXT];
@@ -238,8 +258,13 @@ uint8_t * AddELFSymEntry(uint8_t * buf, SYM * sym, int globflag)
                st_shndx = elfHdrNum[ES_DATA];
        else if (w1 & BSS)
                st_shndx = elfHdrNum[ES_BSS];
-       else if (globflag)
-               st_shndx = 0;           // Global, not absolute
+       else if (globflag && !(w1 & DEFINED) && (w1 & REFERENCED))
+       {
+               st_shndx = SHN_UNDEF;
+       }                                      // If the symbol is global then probably we
+                                    // don't need to do anything (probably)
+                                    // since we set STB_GLOBAL in st_info above.
+                                    // Unless we need to set it to SHN_COMMON?
 
        D_word(st_shndx);