Re: [PATCH][PR symtab/18148] Properly intern constants into psymtab

[Doug Evans <dje at google dot com>]

Andy Wingo writes:
 > >From 16de9f67e56b5b58ff7923db0d6505d61c766124 Mon Sep 17 00:00:00 2001
 > From: Andy Wingo <wingo@igalia.com>
 > Date: Fri, 20 Mar 2015 11:50:00 +0100
 > Subject: [PATCH] Properly intern constants into psymtab
 > 
 > Variables with a DW_AT_const_value but without a DW_AT_location were not
 > getting added to the partial symbol table.  They are added to the full
 > symbol table, however, when the compilation unit's psymtabs are
 > expanded.
 > 
 > Before:
 > 
 >    (gdb) p one
 >    No symbol "one" in current context.
 >    (gdb) mt flush-symbol-cache
 >    (gdb) mt expand one.c
 >    (gdb) p one
 >    $1 = 1
 > 
 > After:
 > 
 >    (gdb) p one
 >    $1 = 1
 > 
 > To the user it's pretty strange, as depending on whether tab completion
 > has forced expansion of all CUs or not the lookup might succeed, or not
 > if the failure was already added to the symbol cache.
 > 
 > This commit simply makes sure to add constants to the partial symbol
 > tables.
 > 
 > gdb/testsuite/ChangeLog:
 > 
 > 	PR symtab/18148
 > 	* gdb.dwarf2/dw2-intercu.S (one, two): Add variables that have a
 > 	const_value but not a location.
 > 	* gdb.dwarf2/dw2-intercu.exp: Add tests that constants without
 > 	location defined in non-main CUs are visible.
 > 
 > gdb/ChangeLog:
 > 
 > 	PR symtab/18148
 > 	* dwarf2read.c (struct partial_die_info): Add has_const_value
 > 	member.
 > 	(add_partial_symbol): Don't punt on symbols that have const_value
 > 	attributes.
 > 	(read_partial_die): Detect DW_AT_const_value.

LGTM.

Thanks!