Eric Norum <eric@cls.usask.ca> submitted linker script and bsp_specs

for the gen68360 that let it work with ELF and C++ exceptions.  This
was used as the basis for changes to EVERY m68k bsp_specs and linkcmds.
Before this modification is over, the layout of the starting stack,
heap, and workspace will likely be modified for every m68k BSP. Then
they will all be very similar.

2 files changed, 92 insertions, 53 deletions

diff --git a/c/src/lib/libbsp/m68k/gen68340/bsp_specs b/c/src/lib/libbsp/m68k/gen68340/bsp_specs
index 61dac86b53..078f4054fb 100644
--- a/c/src/lib/libbsp/m68k/gen68340/bsp_specs
+++ b/c/src/lib/libbsp/m68k/gen68340/bsp_specs
@@ -16,8 +16,12 @@
 *startfile:
 %{!qrtems: %(old_startfile)} %{qrtems: \
 %{!qrtems_debug: start.o%s} \
-%{qrtems_debug: start_g.o%s}}
+%{qrtems_debug: start_g.o%s} \
+crti.o%s crtbegin.o%s}
 
 *link:
 %{!qrtems: %(old_link)} %{qrtems: -dc -dp -N -e start}
 
+*endfile:
+%{!qrtems: %(old_endfile)} %{qrtems: crtend.o%s crtn.o%s}
+
diff --git a/c/src/lib/libbsp/m68k/gen68340/startup/linkcmds b/c/src/lib/libbsp/m68k/gen68340/startup/linkcmds
index 4dbfa37084..a767a348e0 100644
--- a/c/src/lib/libbsp/m68k/gen68340/startup/linkcmds
+++ b/c/src/lib/libbsp/m68k/gen68340/startup/linkcmds
@@ -24,9 +24,6 @@ OUTPUT_FORMAT(coff-m68k)
 
 /*
  * Declare some sizes.
- * XXX: The assignment of ". += XyzSize;" fails in older gld's if the
- *      number used there is not constant.  If this happens to you, edit
- *      the lines marked XXX below to use a constant value.
  */
 RamSize = DEFINED(RamSize) ? RamSize : 4M;
 HeapSize = DEFINED(HeapSize) ? HeapSize : 0x10000;
@@ -79,77 +76,115 @@ SECTIONS {
          * Text, data and bss segments
          */
         .text : {
-                CREATE_OBJECT_SYMBOLS
                 *(.text)
-                . = ALIGN (16);
 
 		/*
-		 * C++ constructors
+		 * C++ constructors/destructors
+		 */
+		*(.gnu.linkonce.t.*)
+
+		/*
+		 * Initialization and finalization code.
+     		 *
+     		 * Various files can provide initialization and finalization
+		 * functions.  crtbegin.o and crtend.o are two instances. The
+		 * body of these functions are in .init and .fini sections. We
+		 * accumulate the bodies here, and prepend function prologues
+		 * from crti.o and function epilogues from crtn.o. crti.o must
+		 * be linked first; crtn.o must be linked last.  Because these
+		 * are wildcards, it doesn't matter if the user does not
+		 * actually link against crti.o and crtn.o; the linker won't
+		 * look for a file to match a wildcard.  The wildcard also
+		 * means that it doesn't matter which directory crti.o and
+		 * crtn.o are in. 
+		 */
+		PROVIDE (_init = .);
+		*crti.o(.init)
+		*(.init)
+		*crtn.o(.init)
+		PROVIDE (_fini = .);
+		*crti.o(.fini)
+		*(.fini)
+		*crtn.o(.fini)
+
+		/*
+		 * C++ constructors/destructors
+     		 *
+     		 * gcc uses crtbegin.o to find the start of the constructors
+		 * and destructors so we make sure it is first.  Because this
+		 * is a wildcard, it doesn't matter if the user does not
+		 * actually link against crtbegin.o; the linker won't look for
+		 * a file to match a wildcard.  The wildcard also means that
+		 * it doesn't matter which directory crtbegin.o is in. The
+		 * constructor and destructor list are terminated in
+		 * crtend.o.  The same comments apply to it.
 		 */
-		__CTOR_LIST__ = .;
-		LONG((__CTOR_END__ - __CTOR_LIST__) / 4 - 2)
+		. = ALIGN (16);
+		*crtbegin.o(.ctors)
 		*(.ctors)
-		LONG(0)
-		__CTOR_END__ = .;
-		__DTOR_LIST__ = .;
-		LONG((__DTOR_END__ - __DTOR_LIST__) / 4 - 2)
+		*crtend.o(.ctors)
+		*crtbegin.o(.dtors)
 		*(.dtors)
-		LONG(0)
-		__DTOR_END__ = .;
+		*crtend.o(.dtors)
 
-                etext = .;
-                _etext = .;
-        } >rom 
-
-	.eh_fram : {
+		/*
+		 * Exception frame info
+		 */
 		. = ALIGN (16);
-		*(.eh_fram)
-	} >ram
+		*(.eh_frame)
 
-	.gcc_exc : {
+		/*
+		 * Read-only data
+		 */
 		. = ALIGN (16);
-		*(.gcc_exc)
-	} >ram
+		_rodata_start = . ;
+		*(.rodata)
+		*(.gnu.linkonce.r*)
 
-       /*
-        * On-chip memory/peripherals
-        *
-	*/
-        dpram : {
-                m340 = .;
-                _m340 = .;
-                . += (8 * 1024);
+                 . = ALIGN (16);
+                PROVIDE (_etext = .);
         } >ram
-
         .data : {
-                copy_start = .;
+                PROVIDE (_copy_start = .);
                 *(.data)
+		*(.gnu.linkonce.d*)
+		*(.gcc_except_table)
                 . = ALIGN (16);
-                _edata = .;
-                copy_end = .;
+                PROVIDE (_edata = .);
+                PROVIDE (_copy_end = .);
         } >ram
-
         .bss : {
-                M68Kvec = .;
-                _M68Kvec = .;
-                . += (256 * 4);
-                clear_start = .;
+		M68Kvec = .;
+		_M68Kvec = .;
+		. += (256 * 4);
+                PROVIDE (_bss_start = .);
+                PROVIDE (_clear_start = .);
                 *(.bss)
                 *(COMMON)
                 . = ALIGN (16);
-                _end = .;
-
-                _HeapStart = .;
-                __HeapStart = .;
-                . += HeapSize;  /* XXX -- Old gld can't handle this */
-                . += StackSize; /* XXX -- Old gld can't handle this */
-                /* . += 0x10000; */ /* HeapSize for old gld */
-                /* . += 0x1000;  */ /* StackSize for old gld */
+                PROVIDE (end = .);
+
+                . += StackSize;
+                PROVIDE (_stack_init = .);
+
                 . = ALIGN (16);
-                stack_init = .;
+                PROVIDE (_HeapStart = .);
+                . += HeapSize;
+                PROVIDE (_HeapEnd = .);
+
                 clear_end = .;
 
-                _WorkspaceBase = .;
-                __WorkspaceBase = .;
+                PROVIDE (_WorkspaceBase = .);
+        } >ram
+
+       /*
+        * On-chip memory/peripherals
+        *
+	*/
+        dpram : {
+                m340 = .;
+                _m340 = .;
+                . += (8 * 1024);
         } >ram
+
 }