RE: [PATCH v3 6/6] Fortran: Nested functions, add scope parameter.

Wiederhake, Tim
2017-09-08T12:13:40Z

Hi Yao,

Thanks for the feedback!

> -----Original Message-----
> From: Yao Qi [mailto:qiyaoltc@gmail.com]
> Sent: Monday, September 4, 2017 11:58 AM
> To: Wiederhake, Tim <tim.wiederhake@intel.com>
> Cc: gdb-patches@sourceware.org; Bernhard Heckel
> <bernhard.heckel@intel.com>
> Subject: Re: [PATCH v3 6/6] Fortran: Nested functions, add scope
> parameter.
>
> On 17-08-11 13:06:51, Tim Wiederhake wrote:
> > From: Bernhard Heckel <bernhard.heckel@intel.com>
> >
> > In order to avoid name clashing in GDB, we add a scope
> > to nested subroutines. Enveloping function gives the
> > scope.
>
> Hi Tim,
> Is there any reason that you split it from patch #5? IMO, both #5 and
> #6 should be a single patch, and we need a NEWS entry.

I agree. Merged and NEWS entry written.

> According to your patch #5, I think both Ada and Fortran have the similar
> feature here. I think we need to keep semantics same in both languages,
> like, "break func::nest_func"?

Sorry, I don't quite follow you. What is it that you'd like to see changed?

> >
> > ---
> > gdb/doc/gdb.texinfo | 3 ++
> > gdb/dwarf2read.c | 26 +++++++++++-
> > gdb/testsuite/gdb.fortran/nested-funcs.exp | 28 +++++++++++--
> > gdb/testsuite/gdb.fortran/nested-funcs.f90 | 66
> ++++++++++++++++++++++++++++--
> > 4 files changed, 114 insertions(+), 9 deletions(-)
> > mode change 100755 => 100644 gdb/testsuite/gdb.fortran/nested-funcs.f90
> >
> > diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
> > index d098eba..983a570 100644
> > --- a/gdb/doc/gdb.texinfo
> > +++ b/gdb/doc/gdb.texinfo
> > @@ -15259,6 +15259,9 @@ The access component operator. Normally used to
> access elements in derived
> > types. Also suitable for unions. As unions aren't part of regular
> Fortran,
> > this can only happen when accessing a register that uses a gdbarch-
> defined
> > union type.
> > +@item ::
> > +The scope operator. Normally used to access variables in modules or to
> set
> > +breakpoints on subroutines nested in modules or in other (internal)
> subroutines.
> > @end table
> >
> > @node Fortran Defaults
> > diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
> > index 894e6a0..92a9c49 100644
> > --- a/gdb/dwarf2read.c
> > +++ b/gdb/dwarf2read.c
> > @@ -7042,6 +7042,7 @@ partial_die_parent_scope (struct partial_die_info
> *pdi,
> > return NULL;
> > }
> >
> > + /* Internal (nested) subroutines in Fortran get a prefix. */
> > if (pdi->tag == DW_TAG_enumerator)
> > /* Enumerators should not get the name of the enumeration as a
> prefix. */
> > parent->scope = grandparent_scope;
> > @@ -7051,7 +7052,10 @@ partial_die_parent_scope (struct partial_die_info
> *pdi,
> > || parent->tag == DW_TAG_class_type
> > || parent->tag == DW_TAG_interface_type
> > || parent->tag == DW_TAG_union_type
> > - || parent->tag == DW_TAG_enumeration_type)
> > + || parent->tag == DW_TAG_enumeration_type
> > + || (cu->language == language_fortran
> > + && parent->tag == DW_TAG_subprogram
> > + && pdi->tag == DW_TAG_subprogram))
> > {
> > if (grandparent_scope == NULL)
> > parent->scope = parent->name;
> > @@ -8560,8 +8564,13 @@ process_die (struct die_info *die, struct
> dwarf2_cu *cu)
> > case DW_TAG_type_unit:
> > read_type_unit_scope (die, cu);
> > break;
> > - case DW_TAG_entry_point:
> > case DW_TAG_subprogram:
> > + /* Internal subprograms in Fortran get a prefix. */
> > + if (cu->language == language_fortran
> > + && die->parent != NULL
> > + && die->parent->tag == DW_TAG_subprogram)
> > + cu->processing_has_namespace_info = 1;
>
> We need some fall-through annotation to suppress warning in GCC 7.

Thanks, fixed.

> > + case DW_TAG_entry_point:
> > case DW_TAG_inlined_subroutine:
> > read_func_scope (die, cu);
> > break;
> > @@ -20169,6 +20178,19 @@ determine_prefix (struct die_info *die, struct
> dwarf2_cu *cu)
> > return TYPE_TAG_NAME (parent_type);
> > return "";
> > }
> > + case DW_TAG_subprogram:
> > + /* Only internal subroutines in Fortran get a prefix with the name
> > + of the parent's subroutine. */
> > + if (cu->language == language_fortran)
> > + {
> > + if ((die->tag == DW_TAG_subprogram)
> > + && (dwarf2_name (parent, cu) != NULL))
> > + return dwarf2_name (parent, cu);
> > + else
> > + return "";
> > + }
> > + else
> > + return determine_prefix (parent, cu);
> > /* Fall through. */
> > default:
> > return determine_prefix (parent, cu);
> > diff --git a/gdb/testsuite/gdb.fortran/nested-funcs.exp
> b/gdb/testsuite/gdb.fortran/nested-funcs.exp
> > index 4c2ee2a..0c8a416 100644
> > --- a/gdb/testsuite/gdb.fortran/nested-funcs.exp
> > +++ b/gdb/testsuite/gdb.fortran/nested-funcs.exp
> > @@ -31,8 +31,8 @@ if ![runto MAIN__] then {
> > }
> >
> > # Test if we can set a breakpoint in a nested function
> > -gdb_breakpoint "sub_nested_outer"
> > -gdb_continue_to_breakpoint "sub_nested_outer" ".*local_int = 19"
> > +gdb_breakpoint "testnestedfuncs::sub_nested_outer"
> > +gdb_continue_to_breakpoint "testnestedfuncs::sub_nested_outer"
> ".*local_int = 19"
> >
> > # Test if we can access local and
> > # non-local variables defined one level up.
> > @@ -43,13 +43,16 @@ gdb_test "set index = 42"
> > gdb_test "print index" "= 42" "print index at BP_outer, manipulated"
> > gdb_test "print local_int" "= 19" "print local_int in outer function"
> >
> > +
>
> Unnecessary change, multiple instances.

Fixed as well.

>
> > # Non-local variable should be affected in one frame up as well.
> > gdb_test "up"
>
>
> --
> Yao (齐尧)

Regards,
Tim
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