On Thu, 5 Mar 2015, H.J. Lu wrote:
> if test $libc_cv_visibility_attribute = yes; then
> + AC_CACHE_CHECK(linker support for protected data symbol,
> + libc_cv_protected_data,
> + [cat > conftest.c <<EOF
> + int bar __attribute__ ((visibility ("protected"))) = 1;
> +EOF
> + libc_cv_protected_data=no
> + if AC_TRY_COMMAND(${CC-cc} -fPIC -shared conftest.c -o conftest.so); then
Use -nostdlib -nostartfiles on all configure tests involving linking so
that they work correctly in bootstrap configurations, unless there is a
clear reason they cannot work with -nostdlib -nostartfiles (in which case
there should be thorough comments about the issue).
> + cat > conftest.c <<EOF
> + extern int bar;
> + int main (void) { return bar; }
> +EOF
> + if AC_TRY_COMMAND(${CC-cc} conftest.c -o conftest conftest.so); then
Likewise; you may need to use -static as well (or LIBC_TRY_LINK_STATIC).
(Running tests may not work well in a build tree from a bootstrap build at
present, but the principle still applies that the normal case is configure
tests that allow for such configurations and any deviation needs
thoroughly justifying.)
Suppose I configure / build with new binutils but a GCC version without
your patches. What will the results be? That the tests don't build /
run? That they build / run but fail (best avoided if possible)? In
either case, you need clear documentation for architecture maintainers on
what GCC versions (*not* requiring any uncommitted GCC patches) must be
used to identify whether architecture-specific changes are needed and to
test such changes.
@@ -50,6 +50,7 @@ enable-werror = @enable_werror@
have-z-combreloc = @libc_cv_z_combreloc@
have-z-execstack = @libc_cv_z_execstack@
have-Bgroup = @libc_cv_Bgroup@
+have-protected-data = @libc_cv_protected_data@
with-fp = @with_fp@
old-glibc-headers = @old_glibc_headers@
unwind-find-fde = @libc_cv_gcc_unwind_find_fde@
@@ -634,6 +634,7 @@ libc_cv_z_combreloc
ASFLAGS_config
libc_cv_Bgroup
libc_cv_cc_with_libunwind
+libc_cv_protected_data
BISON
INSTALL_INFO
PERL
@@ -5734,6 +5735,45 @@ $as_echo "$libc_cv_visibility_attribute" >&6; }
fi
if test $libc_cv_visibility_attribute = yes; then
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking linker support for protected data symbol" >&5
+$as_echo_n "checking linker support for protected data symbol... " >&6; }
+if ${libc_cv_protected_data+:} false; then :
+ $as_echo_n "(cached) " >&6
+else
+ cat > conftest.c <<EOF
+ int bar __attribute__ ((visibility ("protected"))) = 1;
+EOF
+ libc_cv_protected_data=no
+ if { ac_try='${CC-cc} -fPIC -shared conftest.c -o conftest.so'
+ { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+ (eval $ac_try) 2>&5
+ ac_status=$?
+ $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+ test $ac_status = 0; }; }; then
+ cat > conftest.c <<EOF
+ extern int bar;
+ int main (void) { return bar; }
+EOF
+ if { ac_try='${CC-cc} conftest.c -o conftest conftest.so'
+ { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+ (eval $ac_try) 2>&5
+ ac_status=$?
+ $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+ test $ac_status = 0; }; }; then
+ libc_cv_protected_data=yes
+ fi
+ fi
+ rm -f conftest.*
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_protected_data" >&5
+$as_echo "$libc_cv_protected_data" >&6; }
+else
+ libc_cv_protected_data=no
+fi
+
+
+if test $libc_cv_visibility_attribute = yes; then
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for broken __attribute__((visibility()))" >&5
$as_echo_n "checking for broken __attribute__((visibility()))... " >&6; }
if ${libc_cv_broken_visibility_attribute+:} false; then :
@@ -1220,6 +1220,29 @@ EOF
fi
if test $libc_cv_visibility_attribute = yes; then
+ AC_CACHE_CHECK(linker support for protected data symbol,
+ libc_cv_protected_data,
+ [cat > conftest.c <<EOF
+ int bar __attribute__ ((visibility ("protected"))) = 1;
+EOF
+ libc_cv_protected_data=no
+ if AC_TRY_COMMAND(${CC-cc} -fPIC -shared conftest.c -o conftest.so); then
+ cat > conftest.c <<EOF
+ extern int bar;
+ int main (void) { return bar; }
+EOF
+ if AC_TRY_COMMAND(${CC-cc} conftest.c -o conftest conftest.so); then
+ libc_cv_protected_data=yes
+ fi
+ fi
+ rm -f conftest.*
+ ])
+else
+ libc_cv_protected_data=no
+fi
+AC_SUBST(libc_cv_protected_data)
+
+if test $libc_cv_visibility_attribute = yes; then
AC_CACHE_CHECK(for broken __attribute__((visibility())),
libc_cv_broken_visibility_attribute,
[cat > conftest.c <<EOF
@@ -213,6 +213,13 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
tst-initorder2d \
tst-relsort1mod1 tst-relsort1mod2 tst-array2dep \
tst-array5dep tst-null-argv-lib
+ifeq (yes,$(have-protected-data))
+modules-names += tst-protected1moda tst-protected1modb
+tests += tst-protected1a tst-protected1b
+$(objpfx)tst-protected1a: $(addprefix $(objpfx),tst-protected1moda.so tst-protected1modb.so)
+$(objpfx)tst-protected1b: $(addprefix $(objpfx),tst-protected1modb.so tst-protected1moda.so)
+tst-protected1modb.so-no-z-defs = yes
+endif
ifeq (yesyes,$(have-fpie)$(build-shared))
modules-names += tst-piemod1
tests += tst-pie1 tst-pie2
new file mode 100644
@@ -0,0 +1,153 @@
+/* Test the protected visibility when main is linked with moda and modb
+ in that order:
+ 1. Protected symbols, protected1 and protected2, defined in moda, are
+ used in moda.
+ 2. Symbol, protected1, defined in moda, is also used in main and modb.
+ 3. Symbol, protected2, defined in main, is used in main.
+
+ Copyright (C) 2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* This file must be compiled as PIE to avoid copy relocation when
+ accessing protected symbols defined in shared libaries since copy
+ relocation doesn't work with protected symbols and linker in
+ binutils 2.26 enforces this rule. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "tst-protected1mod.h"
+
+/* Prototype for our test function. */
+extern int do_test (void);
+
+int protected2 = -1;
+
+#define TEST_FUNCTION do_test ()
+
+/* This defines the `main' function and some more. */
+#include <test-skeleton.c>
+
+int
+do_test (void)
+{
+ int res = 0;
+
+ /* Check if we get the same address for the protected data symbol. */
+ if (&protected1 != protected1a_p ())
+ {
+ puts ("`protected1' in main and moda doesn't have same address");
+ res = 1;
+ }
+ if (&protected1 != protected1b_p ())
+ {
+ puts ("`protected1' in main and modb doesn't have same address");
+ res = 1;
+ }
+
+ /* Check if we get the right value for the protected data symbol. */
+ if (protected1 != 3)
+ {
+ puts ("`protected1' in main and moda doesn't have same value");
+ res = 1;
+ }
+
+ /* Check if we get the right value for data defined in executable. */
+ if (protected2 != -1)
+ {
+ puts ("`protected2' in main has the wrong value");
+ res = 1;
+ }
+
+ /* Check `protected1' in moda. */
+ if (!check_protected1 ())
+ {
+ puts ("`protected1' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check `protected2' in moda. */
+ if (!check_protected2 ())
+ {
+ puts ("`protected2' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Set `protected2' in moda to 30. */
+ set_protected2 (300);
+
+ /* Check `protected2' in moda. */
+ if (!check_protected2 ())
+ {
+ puts ("`protected2' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Set `protected1' in moda to 30. */
+ set_protected1a (30);
+
+ /* Check `protected1' in moda. */
+ if (!check_protected1 ())
+ {
+ puts ("`protected1' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check if we get the updated value for the protected data symbol. */
+ if (protected1 != 30)
+ {
+ puts ("`protected1' in main doesn't have the updated value");
+ res = 1;
+ }
+
+ protected2 = -300;
+
+ /* Check `protected2' in moda. */
+ if (!check_protected2 ())
+ {
+ puts ("`protected2' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check if data defined in executable is changed. */
+ if (protected2 != -300)
+ {
+ puts ("`protected2' in main is changed");
+ res = 1;
+ }
+
+ /* Set `protected1' in modb to 40. */
+ set_protected1b (40);
+ set_expected_protected1 (40);
+
+ /* Check `protected1' in moda. */
+ if (!check_protected1 ())
+ {
+ puts ("`protected1' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check if we get the updated value for the protected data symbol. */
+ if (protected1 != 40)
+ {
+ puts ("`protected1' in main doesn't have the updated value");
+ res = 1;
+ }
+
+ return res;
+}
new file mode 100644
@@ -0,0 +1,152 @@
+/* Test the protected visibility when main is linked with modb and moda
+ in that order:
+ 1. Protected symbols, protected1 and protected2, defined in moda, are
+ used in moda.
+ 2. Symbol, protected1, defined in modb, is used in main and modb.
+ 3. Symbol, protected2, defined in main, is used in main.
+
+ Copyright (C) 2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* This file must be compiled as PIE to avoid copy relocation when
+ accessing protected symbols defined in shared libaries since copy
+ relocation doesn't work with protected symbols and linker in
+ binutils 2.26 enforces this rule. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "tst-protected1mod.h"
+
+/* Prototype for our test function. */
+extern int do_test (void);
+
+int protected2 = -1;
+
+#define TEST_FUNCTION do_test ()
+
+/* This defines the `main' function and some more. */
+#include <test-skeleton.c>
+
+int
+do_test (void)
+{
+ int res = 0;
+
+ /* Check if we get the same address for the protected data symbol. */
+ if (&protected1 == protected1a_p ())
+ {
+ puts ("`protected1' in main and moda has same address");
+ res = 1;
+ }
+ if (&protected1 != protected1b_p ())
+ {
+ puts ("`protected1' in main and modb doesn't have same address");
+ res = 1;
+ }
+
+ /* Check if we get the right value for the protected data symbol. */
+ if (protected1 != -3)
+ {
+ puts ("`protected1' in main and modb doesn't have same value");
+ res = 1;
+ }
+
+ /* Check if we get the right value for data defined in executable. */
+ if (protected2 != -1)
+ {
+ puts ("`protected2' in main has the wrong value");
+ res = 1;
+ }
+
+ /* Check `protected1' in moda. */
+ if (!check_protected1 ())
+ {
+ puts ("`protected1' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check `protected2' in moda. */
+ if (!check_protected2 ())
+ {
+ puts ("`protected2' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Set `protected2' in moda to 30. */
+ set_protected2 (300);
+
+ /* Check `protected2' in moda. */
+ if (!check_protected2 ())
+ {
+ puts ("`protected2' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Set `protected1' in moda to 30. */
+ set_protected1a (30);
+
+ /* Check `protected1' in moda. */
+ if (!check_protected1 ())
+ {
+ puts ("`protected1' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check if we get the same value for the protected data symbol. */
+ if (protected1 != -3)
+ {
+ puts ("`protected1' in main has the wrong value");
+ res = 1;
+ }
+
+ protected2 = -300;
+
+ /* Check `protected2' in moda. */
+ if (!check_protected2 ())
+ {
+ puts ("`protected2' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check if data defined in executable is changed. */
+ if (protected2 != -300)
+ {
+ puts ("`protected2' in main is changed");
+ res = 1;
+ }
+
+ /* Set `protected1' in modb to 40. */
+ set_protected1b (40);
+
+ /* Check `protected1' in moda. */
+ if (!check_protected1 ())
+ {
+ puts ("`protected1' in moda has the wrong value");
+ res = 1;
+ }
+
+ /* Check if we get the updated value for the protected data symbol. */
+ if (protected1 != 40)
+ {
+ puts ("`protected1' in main doesn't have the updated value");
+ res = 1;
+ }
+
+ return res;
+}
new file mode 100644
@@ -0,0 +1,31 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* Prototypes for the functions in the DSOs. */
+extern int protected1;
+extern int protected2;
+
+extern void set_protected1a (int);
+extern void set_protected1b (int);
+extern int *protected1a_p (void);
+extern int *protected1b_p (void);
+
+extern void set_expected_protected1 (int);
+extern int check_protected1 (void);
+
+extern void set_protected2 (int);
+extern int check_protected2 (void);
new file mode 100644
@@ -0,0 +1,64 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include "tst-protected1mod.h"
+
+int protected1 = 3;
+static int expected_protected1 = 3;
+int protected2 = 4;
+static int expected_protected2 = 4;
+
+asm (".protected protected1");
+asm (".protected protected2");
+
+void
+set_protected1a (int i)
+{
+ protected1 = i;
+ set_expected_protected1 (i);
+}
+
+void
+set_expected_protected1 (int i)
+{
+ expected_protected1 = i;
+}
+
+int *
+protected1a_p (void)
+{
+ return &protected1;
+}
+
+int
+check_protected1 (void)
+{
+ return protected1 == expected_protected1;
+}
+
+void
+set_protected2 (int i)
+{
+ protected2 = i;
+ expected_protected2 = i;
+}
+
+int
+check_protected2 (void)
+{
+ return protected2 == expected_protected2;
+}
new file mode 100644
@@ -0,0 +1,33 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <stdlib.h>
+#include "tst-protected1mod.h"
+
+int protected1 = -3;
+
+void
+set_protected1b (int i)
+{
+ protected1 = i;
+}
+
+int *
+protected1b_p (void)
+{
+ return &protected1;
+}