Ada: make verbatim matcher override other language matchers (PR gdb/22670)
authorPedro Alves <palves@redhat.com>
Wed, 10 Jan 2018 20:38:07 +0000 (20:38 +0000)
committerPedro Alves <palves@redhat.com>
Wed, 10 Jan 2018 20:47:37 +0000 (20:47 +0000)
commitc63d3e8d12f0b08cda95f89aa13274defed215f0
tree4e46ac3e784408de56a7b5accb5f735e7fbcd10b
parentd4c2a405cb7535d25b88e9b8dad0e557242950ca
Ada: make verbatim matcher override other language matchers (PR gdb/22670)

A previous patch fixed verbatim matching in the lookup at the minimal
symbol level, but we should also be finding that same symbol through
the partial/full symtab search.

For example, this is what happens if we use "print" instead of
"break":

    (gdb) p <MixedCaseFunc>
    $1 = {<text variable, no debug info>} 0x4024dc <MixedCaseFunc>

Before the C++ wildmatching series, GDB knows that MixedCaseFunc is a
function without parameters, and the expression above means calling
it.  If you try it before having started the inferior, you'd get the
following (expected) error:

    (gdb) print  <MixedCaseFunc>
    You can't do that without a process to debug.

The main idea behind making the name matcher be determined by the
symbol's language is so that C++ (etc.) wildmatching in linespecs
works even if the current language is not C++, as e.g., when you step
through C or assembly code.

Ada's verbatim matching syntax however ("<...>") isn't quite the same.
It is more a property of the current language than of a particular
symbol's language.  We want to support this syntax when debugging an
Ada program, but it's reason of existence is to find non-Ada symbols.
This suggests going back to enabling it depending on current language
instead of language of the symbol being matched.

I'm not entirely happy with the "current_language" reference (though I
think that it's harmless).  I think we could try storing the current
language in the lookup_name_info object, and then convert a bunch of
functions more to pass around lookup_name_info objects instead of
"const char *" names.  I.e., build the lookup_name_info higher up.
I'm not sure about that, I'll have to think more about it.  Maybe
something different will be better.  Meanwhile, this gets us going.

I've extended the testcase to also exercise a no-debug-info function,
for extra coverage of the minsyms-only paths.

gdb/ChangeLog:
2018-01-10  Pedro Alves  <palves@redhat.com>

PR gdb/22670
* dwarf2read.c
(gdb_index_symbol_name_matcher::gdb_index_symbol_name_matcher):
Adjust to use language_get_symbol_name_matcher instead of
language_defn::la_get_symbol_name_matcher.
* language.c (language_get_symbol_name_matcher): If in Ada mode
and the lookup name is a verbatim match, return Ada's matcher.
* language.h (language_get_symbol_name_matcher): Adjust comment.
(ada_lookup_name_info::verbatim_p):: New method.

gdb/testsuite/ChangeLog:
2018-01-10  Pedro Alves  <palves@redhat.com>

PR gdb/22670
* gdb.ada/bp_c_mixed_case.exp: Add intro comment.  Test printing C
functions too.  Test setting breakpoints and printing C functions
with no debug info too.
* gdb.ada/bp_c_mixed_case/qux.c: New file.
gdb/ChangeLog
gdb/dwarf2read.c
gdb/language.c
gdb/language.h
gdb/symtab.h
gdb/testsuite/ChangeLog
gdb/testsuite/gdb.ada/bp_c_mixed_case.exp
gdb/testsuite/gdb.ada/bp_c_mixed_case/foo_h731_021.adb
gdb/testsuite/gdb.ada/bp_c_mixed_case/qux.c [new file with mode: 0644]