gdb/

	STT_GNU_IFUNC reader implementation.
	* elfread.c: Include gdbtypes.h, value.h and infcall.h.
	(SYMBOL_GOT_PLT_SUFFIX, elf_rel_plt_read)
	(elf_objfile_gnu_ifunc_cache_data, struct elf_gnu_ifunc_cache)
	(elf_gnu_ifunc_cache_hash, elf_gnu_ifunc_cache_eq)
	(elf_gnu_ifunc_record_cache, elf_gnu_ifunc_resolve_by_cache)
	(elf_gnu_ifunc_resolve_by_got, elf_gnu_ifunc_resolve_name)
	(elf_gnu_ifunc_resolve_addr): New.
	(elf_symfile_read): Call elf_rel_plt_read.
	(elf_gnu_ifunc_fns): New.
	(_initialize_elfread): Initialize elf_objfile_gnu_ifunc_cache_data.
	Install elf_gnu_ifunc_fns.
	* infcall.c (find_function_return_type): New function.
	(find_function_addr): Resolve TYPE_GNU_IFUNC functions, if possible.
	* minsyms.c (stub_gnu_ifunc_resolve_addr)
	(stub_gnu_ifunc_resolve_name): New functions.
	(stub_gnu_ifunc_fns, gnu_ifunc_fns_p): New variables.
	* symtab.h (struct gnu_ifunc_fns, gnu_ifunc_resolve_addr)
	(gnu_ifunc_resolve_name, gnu_ifunc_fns_p): New.

1 files changed, 28 insertions, 1 deletions

diff --git a/gdb/infcall.c b/gdb/infcall.c
index e07cf00..ca23704 100644
--- a/gdb/infcall.c
+++ b/gdb/infcall.c
@@ -228,6 +228,21 @@ value_arg_coerce (struct gdbarch *gdbarch, struct value *arg,
   return value_cast (type, arg);
 }
 
+/* Return the return type of a function with its first instruction exactly at
+   the PC address.  Return NULL otherwise.  */
+
+static struct type *
+find_function_return_type (CORE_ADDR pc)
+{
+  struct symbol *sym = find_pc_function (pc);
+
+  if (sym != NULL && BLOCK_START (SYMBOL_BLOCK_VALUE (sym)) == pc
+      && SYMBOL_TYPE (sym) != NULL)
+    return TYPE_TARGET_TYPE (SYMBOL_TYPE (sym));
+
+  return NULL;
+}
+
 /* Determine a function's address and its return type from its value.
    Calls error() if the function is not valid for calling.  */
 
@@ -257,7 +272,19 @@ find_function_addr (struct value *function, struct type **retval_type)
     }
   if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
       || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
-    value_type = TYPE_TARGET_TYPE (ftype);
+    {
+      value_type = TYPE_TARGET_TYPE (ftype);
+
+      if (TYPE_GNU_IFUNC (ftype))
+	{
+	  funaddr = gnu_ifunc_resolve_addr (gdbarch, funaddr);
+
+	  /* Skip querying the function symbol if no RETVAL_TYPE has been
+	     asked for.  */
+	  if (retval_type)
+	    value_type = find_function_return_type (funaddr);
+	}
+    }
   else if (TYPE_CODE (ftype) == TYPE_CODE_INT)
     {
       /* Handle the case of functions lacking debugging info.