Add comment regarding BSS_ASM_OP.

From-SVN: r11382

gcc/config/i860/fx2800.h

 /* Target definitions for GNU compiler for Alliant FX/2800
    running Concentrix 2.2
 
-   Copyright (C) 1991 Free Software Foundation, Inc.
+   Copyright (C) 1991, 1996 Free Software Foundation, Inc.
 
    Written by Howard Chu (hyc@hanauma.jpl.nasa.gov).
 
@@ -340,5 +340,6 @@ Boston, MA 02111-1307, USA.  */
 #define ASM_OUTPUT_LABELREF(FILE,NAME) fprintf (FILE, "_%s", NAME)
 #undef ASM_OUTPUT_EXTERNAL_LIBCALL
 
+/* ??? Is this used anywhere?  */
 #undef BSS_ASM_OP
 #define BSS_ASM_OP	"\t.lcomm"

gcc/config/m68k/m68kv4.h

@@ -103,6 +103,7 @@ while (0)
 
 /* Local common symbols are declared to the assembler with ".lcomm" rather
    than ".bss", so override the definition in svr4.h */
+/* ??? svr4.h no longer defines this, and this is only used by m68k/amix.h.  */
 
 #undef BSS_ASM_OP
 #define BSS_ASM_OP	".lcomm"