[binutils-gdb] libctf: make ctf_lookup of symbols by name work in more cases

[Nick Alcock <nix@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=9049b960f2bc7f0cb9db80d255e9fbec9f476f0f

commit 9049b960f2bc7f0cb9db80d255e9fbec9f476f0f
Author: Nick Alcock <nick.alcock@oracle.com>
Date:   Tue Apr 2 16:06:50 2024 +0100

    libctf: make ctf_lookup of symbols by name work in more cases
    
    In particular, we don't need a symbol table if we're looking up a
    symbol by name and that type of symbol has an indexed symtypetab,
    since in that case we get the name from the symtypetab index, not
    from the symbol table.
    
    This lets you do symbol lookups in unlinked object files and unlinked
    dicts written out via libctf's writeout functions.
    
    libctf/
    
            * ctf-lookup.c (ctf_lookup_by_sym_or_name): Allow lookups
            by index even when there is no symtab.

Diff:
---
 libctf/ctf-lookup.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libctf/ctf-lookup.c b/libctf/ctf-lookup.c
index aa251bafb89..f37dd7e45ce 100644
--- a/libctf/ctf-lookup.c
+++ b/libctf/ctf-lookup.c
@@ -1045,7 +1045,9 @@ ctf_lookup_by_sym_or_name (ctf_dict_t *fp, unsigned long symidx,
     }
 
   err = ECTF_NOSYMTAB;
-  if (sp->cts_data == NULL)
+  if (sp->cts_data == NULL && symname == NULL &&
+      ((is_function && !fp->ctf_funcidx_names) ||
+       (!is_function && !fp->ctf_objtidx_names)))
     goto try_parent;
 
   /* This covers both out-of-range lookups by index and a dynamic dict which