loongarch gcc-4.5 build fixes

Yet another case of missing fields in struct initialisation, which
I've replaced with a memset, and some complaints about identifiers
shadowing global declarations.  Fixing the shadowing in
loongarch-parse.y is easy.  This one isn't so easy:
gas/expr.c: In function 'expr':
gas/expr.c:1891:12: error: declaration of 'is_unsigned' shadows a global declaration
include/opcode/loongarch.h:224:14: error: shadowed declaration is here

opcode/loongarch.h declares lots of stuff that shouldn't be made
available to generic gas code, so I've removed that header from
tc-loongarch.h and moved the parts of TC_FORCE_RELOCATION_SUB_LOCAL
and TC_FORCE_RELOCATION_SUB_LOCAL that need LARCH_opts to functions
in tc-loongarch.c

	* config/loongarch-parse.y (loongarch_parse_expr): Rename
        param to avoid shadowing.
	* config/tc-loongarch.c (loongarch_assemble_INSNs): Use memset
	rather than struct initialisation.
	(loongarch_force_relocation_sub_local): New function.
	(loongarch_force_relocation_sub_same): Likewise.
	* config/tc-loongarch.h: Don't include opcode/loongarch.h.
	(loongarch_force_relocation_sub_local): Declare, and..
	(TC_FORCE_RELOCATION_SUB_LOCAL): ..use here.
	(loongarch_force_relocation_sub_same): Declare, and..
	(TC_FORCE_RELOCATION_SUB_SAME): ..use here.

gas/config/loongarch-parse.y

@@ -42,7 +42,7 @@ is_const (struct reloc_info *info)
 }
 
 int
-loongarch_parse_expr (const char *expr,
+loongarch_parse_expr (const char *exp,
 		      struct reloc_info *reloc_stack_top,
 		      size_t max_reloc_num,
 		      size_t *reloc_num,
@@ -52,7 +52,7 @@ loongarch_parse_expr (const char *expr,
   struct yy_buffer_state *buffstate;
   top = reloc_stack_top;
   end = top + max_reloc_num;
-  buffstate = yy_scan_string (expr);
+  buffstate = yy_scan_string (exp);
   ret = yyparse ();
 
   if (ret == 0)

gas/config/tc-loongarch.c

@@ -1398,7 +1398,8 @@ loongarch_assemble_INSNs (char *str, unsigned int expand_from_macro)
       if (*str == '\0')
 	break;
 
-      struct loongarch_cl_insn the_one = { 0 };
+      struct loongarch_cl_insn the_one;
+      memset (&the_one, 0, sizeof (the_one));
       the_one.name = str;
       the_one.expand_from_macro = expand_from_macro;
 
@@ -1499,6 +1500,29 @@ loongarch_force_relocation (struct fix *fixp)
   return generic_force_reloc (fixp);
 }
 
+/* If subsy of BFD_RELOC32/64 and PC in same segment, and without relax
+   or PC at start of subsy or with relax but sub_symbol_segment not in
+   SEC_CODE, we generate 32/64_PCREL.  */
+bool
+loongarch_force_relocation_sub_local (fixS *fixp, segT sec ATTRIBUTE_UNUSED)
+{
+  return !(LARCH_opts.thin_add_sub
+	   && (fixp->fx_r_type == BFD_RELOC_32
+	       || fixp->fx_r_type == BFD_RELOC_64)
+	   && (!LARCH_opts.relax
+	       || (S_GET_VALUE (fixp->fx_subsy)
+		   == fixp->fx_frag->fr_address + fixp->fx_where)
+	       || (S_GET_SEGMENT (fixp->fx_subsy)->flags & SEC_CODE) == 0));
+}
+
+/* Postpone text-section label subtraction calculation until linking, since
+   linker relaxations might change the deltas.  */
+bool
+loongarch_force_relocation_sub_same(fixS *fixp ATTRIBUTE_UNUSED, segT sec)
+{
+  return LARCH_opts.relax && (sec->flags & SEC_CODE) != 0;
+}
+
 static void fix_reloc_insn (fixS *fixP, bfd_vma reloc_val, char *buf)
 {
   reloc_howto_type *howto;

gas/config/tc-loongarch.h

@@ -21,8 +21,6 @@
 #ifndef TC_LOONGARCH
 #define TC_LOONGARCH
 
-#include "opcode/loongarch.h"
-
 #define TARGET_BYTES_BIG_ENDIAN 0
 #define TARGET_ARCH bfd_arch_loongarch
 
@@ -80,26 +78,19 @@ extern int loongarch_force_relocation (struct fix *);
 /* If subsy of BFD_RELOC32/64 and PC in same segment, and without relax
    or PC at start of subsy or with relax but sub_symbol_segment not in
    SEC_CODE, we generate 32/64_PCREL.  */
-#define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEG) \
-  (!(LARCH_opts.thin_add_sub \
-     && ((FIX)->fx_r_type == BFD_RELOC_32 \
-	 ||(FIX)->fx_r_type == BFD_RELOC_64) \
-     && (!LARCH_opts.relax \
-	|| S_GET_VALUE (FIX->fx_subsy) \
-	   == FIX->fx_frag->fr_address + FIX->fx_where \
-	|| (LARCH_opts.relax \
-	   && ((S_GET_SEGMENT (FIX->fx_subsy)->flags & SEC_CODE) == 0)))))
+extern bool loongarch_force_relocation_sub_local (struct fix *, asection *);
+#define TC_FORCE_RELOCATION_SUB_LOCAL(FIX, SEC) \
+  loongarch_force_relocation_sub_local (FIX, SEC)
 
 #define TC_VALIDATE_FIX_SUB(FIX, SEG) 1
 #define DIFF_EXPR_OK 1
 
 /* Postpone text-section label subtraction calculation until linking, since
    linker relaxations might change the deltas.  */
+extern bool loongarch_force_relocation_sub_same(struct fix *, asection *);
 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEC)	\
-  (LARCH_opts.relax ?  \
-    (GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEC)	\
-      || ((SEC)->flags & SEC_CODE) != 0)		\
-    : (GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEC))) \
+  (loongarch_force_relocation_sub_same (FIX, SEC) \
+   || GENERIC_FORCE_RELOCATION_SUB_SAME (FIX, SEC))
 
 #define TC_LINKRELAX_FIXUP(seg) ((seg->flags & SEC_CODE)  \
 				    || (seg->flags & SEC_DEBUGGING))