From: Sébastien Darche <sdarche@efficios.com>
Date: Mon, 20 Oct 2025 19:07:33 +0000 (-0400)
Subject: gdb: lookup minsym using section in find_sal_for_pc_sect
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=37563b8beb5df0a7358fa6780a63edf5d3c447a1;p=thirdparty%2Fbinutils-gdb.git

gdb: lookup minsym using section in find_sal_for_pc_sect

The find_sal_for_pc_sect function attempts to find the line that is
closest to a pc+section in the available symbols. One of the first thing
the function does is search for a bound minimal symbol corresponding to
that pc. In its original version, the lookup is performed by
lookup_minimal_symbol_by_pc, discarding the section. This is misleading
and may cause issues with overlay debugging if a second minsym with the
same pc (but a different section) can be found -- although this is only
in theory after inspecting the code, as I have no way to test this on a
system supporting overlays.

This should have no observable effects for the end user. One slight
benefit is that we can avoid a section lookup inside
lookup_minimal_symbol_by_pc_section if the caller does provide a
section.

Since the section is already passed as an argument to the function, the
proposed change forwards this section to the minsym lookup section.

Approved-By: Tom Tromey <tom@tromey.com>
Change-Id: I86a16bf397ea7167d3e9c7db79b8d7901fad1a97
---

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 2b54d245b86..0ddb25f2879 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -2965,7 +2965,7 @@ find_sal_for_pc_sect (CORE_ADDR pc, struct obj_section *section, int notcurrent)
    * rather than the stub address.
    *
    * Assumptions being made about the minimal symbol table:
-   *   1. lookup_minimal_symbol_by_pc() will return a trampoline only
+   *   1. lookup_minimal_symbol_by_pc_section() will return a trampoline only
    *      if we're really in the trampoline.s If we're beyond it (say
    *      we're in "foo" in the above example), it'll have a closer
    *      symbol (the "foo" text symbol for example) and will not
@@ -2976,7 +2976,7 @@ find_sal_for_pc_sect (CORE_ADDR pc, struct obj_section *section, int notcurrent)
    *      check for the address being the same, to avoid an
    *      infinite recursion.
    */
-  bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc (pc);
+  bound_minimal_symbol msymbol = lookup_minimal_symbol_by_pc_section (pc, section);
   if (msymbol.minsym != NULL)
     if (msymbol.minsym->type () == mst_solib_trampoline)
       {