Re: [PATCH] Gold: Do not emit locals from discard .eh_frame sections.

[Ian Lance Taylor <iant at google dot com>]

"Doug Kwan (éæå)" <dougkwan@google.com> writes:

> 2009-06-04  Doug Kwan  <dougkwan@google.com>
>
>         * object.cc (Sized_relobj::Sized_relobj): Initialize
>         discarded_eh_frame_shndx_ to -1U.
>         (Sized_relobj::do_layout): Record index of a discard .eh_frame
>         section.
>         (Sized_relobj::do_count_local_symbols): Skip local symbols in
>         a discarded .eh_frame section.
>         (Sized_relobj::do_finalize_local_symbols): Ditto.
>         * object.h (class Sized_relobj): Declare new member
>         discarded_eh_frame_shndx_.
>         * testsuite/Makefile.am (check_PROGRAMS): Add local_labels_test.
>         (local_labels_test_SOURCE, local_labels_test_LDFLAGS): Define new.
>         (local_labels_test.o): New rule.
>         * testsuite/Makefile.in: Regenerate.
>         * testsuite/local_labels_test.cc: New file.


> +	  // There can be at most one .eh_frame section per object.
> +	  gold_assert(this->discarded_eh_frame_shndx_ == -1U);
> +	  this->discarded_eh_frame_shndx_ = i;
> +	  out_section_offsets[i] = invalid_address;

Reading the comment literally makes the loop seem unnecessary.  Change
it to say "An object can contain at most one section holding exception
frame information."


> +  // If this object has a GNU sytle .eh_frame section that is discarded in
> +  // output, record the index here.  Otherwise it is -1U.

s/sytle/style/


> +check_PROGRAMS += local_labels_test
> +local_labels_test_SOURCES = local_labels_test.cc
> +local_labels_test_LDFLAGS = -Bgcctestdir/
> +local_labels_test.o: local_labels_test.cc
> +	$(CXXCOMPILE) -g -c -Wa,--keep-locals -o $@ $<

Use -L here instead of --keep-locals.  -L is supported by many
assemblers, --keep-locals is only supported by gas.  We may need to use
a configure test for this, but let's see if we can get away with -L.

Instead of introducing a new nearly-empty .cc file, just have this test
compile basic_test.cc with the -L option.

Ian