Fix --defsym to copy symbol attributes.

Alan Modra committed a patch to Gnu ld to fix a problem encountered on
PPC where the --defsym option wasn't copying the st_other bits to the
newly-defined symbol.

    https://sourceware.org/ml/binutils/2014-07/msg00094.html

Gold has the same problem, and additionally wasn't copying the symbol type.
This patch fixes both problems, by copying the symbol type, visibility, and
the remaining st_other bits to the new symbol for --defsym=sym1=sym2
assignments.

gold/
	* expression.cc (struct Expression::Expression_eval_info): Add
	new fields type_pointer, vis_pointer, and nonvis_pointer.
	(Expression::eval_maybe_dot): Add type_pointer, vis_pointer, and
	nonvis_pointer parameters. Adjust all calls.
	(Symbol_expression::value): Update type, visibility, and nonvis bits
	in caller.
	* script.cc (Symbol_assignment::sized_finalize): Update type,
	visibility, and remaining st_other bits for new symbol.
	* script.h: (Expression::eval_maybe_dot): Add type_pointer,
	vis_pointer, and nonvis_pointer parameters.
	* symtab.h (Symbol::set_type): New method.

	* testsuite/Makefile.am (defsym_test): New test.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/defsym_test.c: New file.
	* testsuite/defsym_test.sh: New file.
This commit is contained in:
Cary Coutant 2014-07-08 22:34:27 -07:00
parent ecf3e831f7
commit e051745c83
9 changed files with 159 additions and 8 deletions

View File

@ -1,3 +1,22 @@
2014-07-08 Cary Coutant <ccoutant@google.com>
* expression.cc (struct Expression::Expression_eval_info): Add
new fields type_pointer, vis_pointer, and nonvis_pointer.
(Expression::eval_maybe_dot): Add type_pointer, vis_pointer, and
nonvis_pointer parameters. Adjust all calls.
(Symbol_expression::value): Update type, visibility, and nonvis bits
in caller.
* script.cc (Symbol_assignment::sized_finalize): Update type,
visibility, and remaining st_other bits for new symbol.
* script.h: (Expression::eval_maybe_dot): Add type_pointer,
vis_pointer, and nonvis_pointer parameters.
* symtab.h (Symbol::set_type): New method.
* testsuite/Makefile.am (defsym_test): New test.
* testsuite/Makefile.in: Regenerate.
* testsuite/defsym_test.c: New file.
* testsuite/defsym_test.sh: New file.
2014-07-08 Cary Coutant <ccoutant@google.com>
PR gold/15639

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@ -68,6 +68,12 @@ struct Expression::Expression_eval_info
Output_section** result_section_pointer;
// Pointer to where the alignment of the result should be stored.
uint64_t* result_alignment_pointer;
// Pointer to where the type of the symbol on the RHS should be stored.
elfcpp::STT* type_pointer;
// Pointer to where the visibility of the symbol on the RHS should be stored.
elfcpp::STV* vis_pointer;
// Pointer to where the rest of the symbol's st_other field should be stored.
unsigned char* nonvis_pointer;
};
// Evaluate an expression.
@ -76,8 +82,8 @@ uint64_t
Expression::eval(const Symbol_table* symtab, const Layout* layout,
bool check_assertions)
{
return this->eval_maybe_dot(symtab, layout, check_assertions,
false, 0, NULL, NULL, NULL, false);
return this->eval_maybe_dot(symtab, layout, check_assertions, false, 0,
NULL, NULL, NULL, NULL, NULL, NULL, false);
}
// Evaluate an expression which may refer to the dot symbol.
@ -92,7 +98,7 @@ Expression::eval_with_dot(const Symbol_table* symtab, const Layout* layout,
{
return this->eval_maybe_dot(symtab, layout, check_assertions, true,
dot_value, dot_section, result_section_pointer,
result_alignment_pointer,
result_alignment_pointer, NULL, NULL, NULL,
is_section_dot_assignment);
}
@ -105,6 +111,9 @@ Expression::eval_maybe_dot(const Symbol_table* symtab, const Layout* layout,
uint64_t dot_value, Output_section* dot_section,
Output_section** result_section_pointer,
uint64_t* result_alignment_pointer,
elfcpp::STT* type_pointer,
elfcpp::STV* vis_pointer,
unsigned char* nonvis_pointer,
bool is_section_dot_assignment)
{
Expression_eval_info eei;
@ -121,6 +130,12 @@ Expression::eval_maybe_dot(const Symbol_table* symtab, const Layout* layout,
*result_section_pointer = NULL;
eei.result_section_pointer = result_section_pointer;
// For symbol=symbol assignments, we need to track the type, visibility,
// and remaining st_other bits.
eei.type_pointer = type_pointer;
eei.vis_pointer = vis_pointer;
eei.nonvis_pointer = nonvis_pointer;
eei.result_alignment_pointer = result_alignment_pointer;
uint64_t val = this->value(&eei);
@ -196,6 +211,12 @@ Symbol_expression::value(const Expression_eval_info* eei)
if (eei->result_section_pointer != NULL)
*eei->result_section_pointer = sym->output_section();
if (eei->type_pointer != NULL)
*eei->type_pointer = sym->type();
if (eei->vis_pointer != NULL)
*eei->vis_pointer = sym->visibility();
if (eei->nonvis_pointer != NULL)
*eei->nonvis_pointer = sym->nonvis();
if (parameters->target().get_size() == 32)
return eei->symtab->get_sized_symbol<32>(sym)->value();
@ -271,6 +292,9 @@ class Unary_expression : public Expression
eei->dot_section,
arg_section_pointer,
eei->result_alignment_pointer,
NULL,
NULL,
NULL,
false);
}
@ -351,6 +375,9 @@ class Binary_expression : public Expression
eei->dot_section,
section_pointer,
alignment_pointer,
NULL,
NULL,
NULL,
false);
}
@ -366,6 +393,9 @@ class Binary_expression : public Expression
eei->dot_section,
section_pointer,
alignment_pointer,
NULL,
NULL,
NULL,
false);
}
@ -517,6 +547,9 @@ class Trinary_expression : public Expression
eei->dot_section,
section_pointer,
NULL,
NULL,
NULL,
NULL,
false);
}
@ -532,6 +565,9 @@ class Trinary_expression : public Expression
eei->dot_section,
section_pointer,
alignment_pointer,
NULL,
NULL,
NULL,
false);
}
@ -547,6 +583,9 @@ class Trinary_expression : public Expression
eei->dot_section,
section_pointer,
alignment_pointer,
NULL,
NULL,
NULL,
false);
}

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@ -980,12 +980,19 @@ Symbol_assignment::sized_finalize(Symbol_table* symtab, const Layout* layout,
Output_section* dot_section)
{
Output_section* section;
elfcpp::STT type = elfcpp::STT_NOTYPE;
elfcpp::STV vis = elfcpp::STV_DEFAULT;
unsigned char nonvis = 0;
uint64_t final_val = this->val_->eval_maybe_dot(symtab, layout, true,
is_dot_available,
dot_value, dot_section,
&section, NULL, false);
&section, NULL, &type,
&vis, &nonvis, false);
Sized_symbol<size>* ssym = symtab->get_sized_symbol<size>(this->sym_);
ssym->set_value(final_val);
ssym->set_type(type);
ssym->set_visibility(vis);
ssym->set_nonvis(nonvis);
if (section != NULL)
ssym->set_output_section(section);
}
@ -1005,7 +1012,7 @@ Symbol_assignment::set_if_absolute(Symbol_table* symtab, const Layout* layout,
uint64_t val = this->val_->eval_maybe_dot(symtab, layout, false,
is_dot_available, dot_value,
dot_section, &val_section, NULL,
false);
NULL, NULL, NULL, false);
if (val_section != NULL && val_section != dot_section)
return;

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@ -34,6 +34,7 @@
#include <string>
#include <vector>
#include "elfcpp.h"
#include "script-sections.h"
namespace gold
@ -111,6 +112,7 @@ class Expression
bool is_dot_available, uint64_t dot_value,
Output_section* dot_section,
Output_section** result_section, uint64_t* result_alignment,
elfcpp::STT* type, elfcpp::STV* vis, unsigned char* nonvis,
bool is_section_dot_assignment);
// Print the expression to the FILE. This is for debugging.

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@ -215,6 +215,11 @@ class Symbol
type() const
{ return this->type_; }
// Set the symbol type.
void
set_type(elfcpp::STT type)
{ this->type_ = type; }
// Return true for function symbol.
bool
is_func() const

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@ -2253,6 +2253,17 @@ ehdr_start_test_5_CXXFLAGS = -DEHDR_START_USER_DEF
ehdr_start_test_5_LDFLAGS = -Bgcctestdir/
ehdr_start_test_5_LDADD =
# Test that the --defsym option copies the symbol type and visibility.
check_SCRIPTS += defsym_test.sh
check_DATA += defsym_test.syms
MOSTLYCLEANFILES += defsym_test.syms
defsym_test.syms: defsym_test
$(TEST_READELF) -sW $< > $@
defsym_test: defsym_test.o gcctestdir/ld
$(LINK) -Bgcctestdir/ -Wl,--defsym=bar=foo defsym_test.o
defsym_test.o: defsym_test.c
$(COMPILE) -c -o $@ $<
# End-to-end incremental linking tests.
# Incremental linking is currently supported only on the x86_64 target.

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@ -568,9 +568,14 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
# Test that __ehdr_start is left undefined when the text segment is not
# appropriately aligned.
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_70 = ehdr_start_test_4.sh
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_71 = ehdr_start_test_4.syms
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_72 = ehdr_start_test_4
# Test that the --defsym option copies the symbol type and visibility.
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_70 = ehdr_start_test_4.sh \
@GCC_TRUE@@NATIVE_LINKER_TRUE@ defsym_test.sh
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_71 = ehdr_start_test_4.syms \
@GCC_TRUE@@NATIVE_LINKER_TRUE@ defsym_test.syms
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_72 = ehdr_start_test_4 \
@GCC_TRUE@@NATIVE_LINKER_TRUE@ defsym_test.syms
@GCC_FALSE@ehdr_start_test_5_DEPENDENCIES =
@NATIVE_LINKER_FALSE@ehdr_start_test_5_DEPENDENCIES =
@ -4132,6 +4137,8 @@ gdb_index_test_4.sh.log: gdb_index_test_4.sh
@p='gdb_index_test_4.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
ehdr_start_test_4.sh.log: ehdr_start_test_4.sh
@p='ehdr_start_test_4.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
defsym_test.sh.log: defsym_test.sh
@p='defsym_test.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
script_test_10.sh.log: script_test_10.sh
@p='script_test_10.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
split_i386.sh.log: split_i386.sh
@ -5600,6 +5607,12 @@ uninstall-am:
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXLINK) -Bgcctestdir/ -Wl,-Ttext=0x100100 $<
@GCC_TRUE@@NATIVE_LINKER_TRUE@ehdr_start_test_4.o: ehdr_start_test.cc
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXCOMPILE) -c -DEHDR_START_WEAK -o $@ $<
@GCC_TRUE@@NATIVE_LINKER_TRUE@defsym_test.syms: defsym_test
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(TEST_READELF) -sW $< > $@
@GCC_TRUE@@NATIVE_LINKER_TRUE@defsym_test: defsym_test.o gcctestdir/ld
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(LINK) -Bgcctestdir/ -Wl,--defsym=bar=foo defsym_test.o
@GCC_TRUE@@NATIVE_LINKER_TRUE@defsym_test.o: defsym_test.c
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(COMPILE) -c -o $@ $<
# End-to-end incremental linking tests.
# Incremental linking is currently supported only on the x86_64 target.

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@ -0,0 +1,15 @@
#include <stdio.h>
void foo (void) __attribute__ ((noinline, visibility ("hidden")));
void foo (void) {
printf("foo called.\n");
}
void bar(void);
int main(void) {
foo();
bar();
return 0;
}

40
gold/testsuite/defsym_test.sh Executable file
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@ -0,0 +1,40 @@
#!/bin/sh
# defsym_test.sh -- test that --defsym copies type and visiblity.
# Copyright (C) 2014 Free Software Foundation, Inc.
# Written by Cary Coutant <ccoutant@google.com>.
# This file is part of gold.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
# MA 02110-1301, USA.
check()
{
if ! grep -q "$2" "$1"
then
echo "Did not find expected symbol in $1:"
echo " $2"
echo ""
echo "Actual output below:"
cat "$1"
exit 1
fi
}
check defsym_test.syms "FUNC *GLOBAL *HIDDEN *[0-9]* *bar"
exit 0