[PATCH] Dwarf: fix build with old gcc

[Jan Beulich]

4.3-ish warns about a possibly uninitialized variable, which results in
a build failure due to -Werror.

binutils/
2021-02-15  Jan Beulich  <jbeulich@suse.com>

	* dwarf.c (process_debug_info): Initialize "dwo_id".

--- a/binutils/dwarf.c
+++ b/binutils/dwarf.c
@@ -3693,7 +3693,7 @@ process_debug_info (struct dwarf_section
 	SAFE_BYTE_GET_AND_INC (compunit.cu_pointer_size, hdrptr, 1, end);
 
       bfd_boolean do_dwo_id = FALSE;
-      uint64_t dwo_id;
+      uint64_t dwo_id = 0;
       if (compunit.cu_unit_type == DW_UT_split_compile
 	  || compunit.cu_unit_type == DW_UT_skeleton)
 	{