gdb: fix ia64-tdep.c build with g++ 4.8

When building with g++ 4.8, I get:

      CXX    ia64-tdep.o
    /home/smarchi/src/binutils-gdb/gdb/ia64-tdep.c:3862:1: error: could not convert '{ia64_allocate_new_rse_frame, ia64_store_argument_in_slot, ia64_set_function_addr}' from '<brace
-enclosed initializer list>' to 'const ia64_infcall_ops'
     };
     ^

This happens since commit 345bd07cce3 ("gdb: fix gdbarch_tdep ODR
violation"), which added default values for ia64_infcall_ops fields.  It
looks like g++ 4.8 doesn't like initializing the ia64_infcall_ops object
using the brace-enclosed initializer list when the ia64_infcall_ops
fields are assigned default values.

Later compilers don't have a problem with that, so I suppose that the
code is correct, but still, change it to make gcc 4.8 happy.  Don't
initialize the fields of ia64_infcall_ops directly, instead
default-initialize ia64_gdbarch_tdep::infcall_ops.

Change-Id: I35e3a61abd7b7bbcafe6cb207078c738c5266d76

1 files changed, 4 insertions, 5 deletions

diff --git a/gdb/ia64-tdep.h b/gdb/ia64-tdep.h
index 82319d5..d831484 100644
--- a/gdb/ia64-tdep.h
+++ b/gdb/ia64-tdep.h
@@ -216,18 +216,17 @@ struct ia64_infcall_ops
 
      Should do nothing if this operation is not permitted by the OS.  */
   void (*allocate_new_rse_frame) (struct regcache *regcache, ULONGEST bsp,
-				  int sof) = nullptr;
+				  int sof);
 
   /* Store the argument stored in BUF into the appropriate location
      given the BSP and the SLOTNUM.  */
   void (*store_argument_in_slot) (struct regcache *regcache, CORE_ADDR bsp,
-				  int slotnum, gdb_byte *buf) = nullptr;
+				  int slotnum, gdb_byte *buf);
 
   /* For targets where we cannot call the function directly, store
      the address of the function we want to call at the location
      expected by the calling sequence.  */
-  void (*set_function_addr) (struct regcache *regcache, CORE_ADDR func_addr)
-    = nullptr;
+  void (*set_function_addr) (struct regcache *regcache, CORE_ADDR func_addr);
 };
 
 struct ia64_gdbarch_tdep : gdbarch_tdep
@@ -255,7 +254,7 @@ struct ia64_gdbarch_tdep : gdbarch_tdep
   /* ISA-specific data types.  */
   struct type *ia64_ext_type = nullptr;
 
-  struct ia64_infcall_ops infcall_ops;
+  struct ia64_infcall_ops infcall_ops {};
 };
 
 extern void ia64_write_pc (struct regcache *, CORE_ADDR);