[Ada] Add support for subprogram renamings
authorPierre-Marie de Rodat <derodat@adacore.com>
Wed, 22 Jul 2015 13:30:57 +0000 (15:30 +0200)
committerPierre-Marie de Rodat <derodat@adacore.com>
Thu, 13 Aug 2015 07:33:42 +0000 (09:33 +0200)
commit22cee43f9af76fc4c10c3d4018a9ada6d7c5c1a5
treeed55bfc1342e44a3889337a8106eb75c21ccfad1
parent19c2883a9b92e2be695368e19788fd0210d732d4
[Ada] Add support for subprogram renamings

Consider the following declaration:

    function Foo (I : Integer) return Integer renames Pack.Bar;

As Foo is not materialized as a routine whose name is derived from Foo,
GDB currently cannot use it:

    (gdb) print foo(0)
    No definition of "foo" in current context.

However, compilers can emit DW_TAG_imported_declaration in order to
materialize the fact that Foo is actually another name for Pack.Bar.
This commit enhances the DWARF reader to record global renamings (it
used to put global ones in a static block) and enhances the Ada engine
to leverage this information during symbol lookup.

gdb/ChangeLog:

* ada-lang.c: Include namespace.h
(aux_add_nonlocal_symbols): Fix a function name in comment.
(ada_add_block_renamings): New.
(add_nonlocal_symbols): Add global renamings handling.
(ada_lookup_symbol_list_worker): Move the symbol lookup part
to...
(ada_add_all_symbols): ... this new function.
(ada_add_block_symbols): Try to match the input name against the
"using directives list", perform a recursive symbol lookup on
the matched declarations.
* block.h (struct block): Move the_namespace to top-level as
namespace_info. Remove the language_specific field.
(BLOCK_NAMESPACE): Update access to the namespace_info field.
* buildsym.h (using_directives): Rename into...
(local_using_directives): ... this.
(global_using_directives): New.
(struct context_stack): Rename the using_directives field into
local_using_directives.
* buildsym.c (finish_block_internal): Deal with the proper
using directives repository (local or global).
(prepare_for_building): Reset local_using_directives. Assert
that there is no pending global using directive.
(reset_symtab_globals): Reset global_using_directives and
local_using_directives.
(end_symtab_get_static_block): Don't ignore symtabs that have
only using directives.
(push_context): Update references to local_using_directives.
(buildsym_init): Do not reset using_directives.
* cp-support.c: Include namespace.h.
* cp-support.h (struct using_direct): Move to namespace.h.
(cp_add_using_directives): Move to namespace.h.
* cp-namespace.c: Include namespace.h
(cp_add_using_directive): Move to namespace.c, rename it to
add_using_directive, add a "using_directives" argument and use
it as the pending using directives repository.  All callers
updated.
* dwarf2read.c (using_directives): New.
(read_import_statement): Call using_directives.
(read_func_scope): Update references to local_using_directives.
(read_lexical_block_scope): Likewise.
(read_namespace): Update the heading comment, call
using_directives.
* namespace.h: New file.
* namespace.c: New file.
* Makefile.in (SFILES): Add namespace.c.
(COMMON_OBS): Add namespace.o

gdb/testsuite/ChangeLog:

* gdb.ada/fun_renaming.exp: New testcase.
* gdb.ada/fun_renaming/fun_renaming.adb: New file.
* gdb.ada/fun_renaming/pack.adb: New file.
* gdb.ada/fun_renaming/pack.ads: New file.

Tested on x86_64-linux.  Support for this in GCC is in the pipeline: see
<https://gcc.gnu.org/ml/gcc-patches/2015-07/msg02166.html>.
15 files changed:
gdb/Makefile.in
gdb/ada-lang.c
gdb/block.h
gdb/buildsym.c
gdb/buildsym.h
gdb/cp-namespace.c
gdb/cp-support.c
gdb/cp-support.h
gdb/dwarf2read.c
gdb/namespace.c [new file with mode: 0644]
gdb/namespace.h [new file with mode: 0644]
gdb/testsuite/gdb.ada/fun_renaming.exp [new file with mode: 0644]
gdb/testsuite/gdb.ada/fun_renaming/fun_renaming.adb [new file with mode: 0644]
gdb/testsuite/gdb.ada/fun_renaming/pack.adb [new file with mode: 0644]
gdb/testsuite/gdb.ada/fun_renaming/pack.ads [new file with mode: 0644]