[Bug exp/34201] [gdb/exp] Namespace variable not found when stopped at inlined function call

https://sourceware.org/bugzilla/show_bug.cgi?id=34201

--- Comment #2 from Sourceware Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tom de Vries <[email protected]>:

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=2ce366ef2aa4b547362617be339765c6f0de3fb2

commit 2ce366ef2aa4b547362617be339765c6f0de3fb2
Author: Tom de Vries <[email protected]>
Date:   Mon Jul 13 19:09:35 2026 +0200

    [gdb/exp] Fix ns var lookup when stopped at inlined fn call

    Consider test.c:
    ...
         1  namespace mod_a {
         2    int xxx = 10;
         3  }
         4
         5  static inline int __attribute__((always_inline))
         6  inlined () {
         7    return 0;
         8  }
         9
        10  int main () {
        11    using namespace mod_a;
        12    int res = inlined ();
        13    return res + xxx;
        14  }
    ...
    compiled with "g++ test.c -g".

    Trying to print variable xxx at line 12 fails:
    ...
    $ gdb -q -batch a.out -ex start -ex "p xxx"
      ...
    Temporary breakpoint 1, main () at test.c:12
    12        int res = inlined ();
    No symbol "xxx" in current context.
    ...

    The problem is here in function using_direct::valid_line:
    ...
          CORE_ADDR curr_pc = get_frame_pc (get_selected_frame (nullptr));
          symtab_and_line curr_sal = find_sal_for_pc (curr_pc, 0);
          return (decl_line <= curr_sal.line)
                 || (decl_line >= boundary);
    ...
    where we're trying to decide whether "using namespace mod_a" is applicable.

    The decl_line is 11, as expected.

    If curr_sal.line were 12, decl_line <= curr_sal.line would be true, and
    using_direct::valid_line would return true.

    But instead, curr_sal.line is 7.

    This is sort of correct, the current PC maps to that line.  It's just that
gdb
    steps into inlined functions in two steps, each with identical PC:
    - once stopping at the call site (line 12 in this case)
    - once stopping at the PC line (line 7 in this case)

    The function using_direct::valid_line doesn't apply this logic, and
    consequently line 7 is used for both cases.

    Fix this by using find_frame_sal instead.

    Tested on x86_64-linux.

    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=34201

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