diff options
| -rw-r--r-- | ChangeLog | 4 | ||||
| -rwxr-xr-x | configure | 67 | ||||
| -rw-r--r-- | configure.in | 58 |
3 files changed, 124 insertions, 5 deletions
@@ -1,5 +1,9 @@ 2011-07-02 Roland McGrath <roland@hack.frob.com> + * configure.in (use-default-link): Default to yes if a test -shared + link meets our qualifications. + * configure: Regenerated. + * config.make.in (output-format): New variable. * configure.in: Check for ld --print-output-format support. * configure: Regenerated. @@ -1469,7 +1469,7 @@ Optional Packages: --without-cvs if CVS should not be used --with-headers=PATH location of system headers to use (for example /usr/src/linux/include) [default=compiler default] - --with-default-link do not use explicit linker scripts [default=no] + --with-default-link do not use explicit linker scripts --with-tls enable support for TLS --without-__thread do not use TLS features even when supporting them --with-cpu=CPU select code for CPU variant @@ -3593,7 +3593,7 @@ fi if test "${with_default_link+set}" = set; then : withval=$with_default_link; use_default_link=$withval else - use_default_link=no + use_default_link=default fi @@ -6702,6 +6702,69 @@ fi { $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_hashstyle" >&5 $as_echo "$libc_cv_hashstyle" >&6; } + + # The linker's default -shared behavior is good enough if it + # does these things that our custom linker scripts ensure that + # all allocated NOTE sections come first. + if test "$use_default_link" = default; then + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sufficient default -shared layout" >&5 +$as_echo_n "checking for sufficient default -shared layout... " >&6; } +if ${libc_cv_use_default_link+:} false; then : + $as_echo_n "(cached) " >&6 +else + libc_cv_use_default_link=no + cat > conftest.s <<\EOF + .section .note.a,"a",%note + .balign 4 + .long 4,4,9 + .string "GNU" + .string "foo" + .section .note.b,"a",%note + .balign 4 + .long 4,4,9 + .string "GNU" + .string "bar" +EOF + if { ac_try=' ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&5' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } && + ac_try=`$READELF -S conftest.so | sed -n \ + '${x;p;} + s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/ + t a + b + : a + H'` + then + libc_seen_a=no libc_seen_b=no + set -- $ac_try + while test $# -ge 2 -a "$1" = NOTE; do + case "$2" in + .note.a) libc_seen_a=yes ;; + .note.b) libc_seen_b=yes ;; + esac + shift 2 + done + case "$libc_seen_a$libc_seen_b" in + yesyes) + libc_cv_use_default_link=yes + ;; + *) + echo >&5 "\ +$libc_seen_a$libc_seen_b from: +$ac_try" + ;; + esac + fi + rm -f conftest* +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_use_default_link" >&5 +$as_echo "$libc_cv_use_default_link" >&6; } + use_default_link=$libc_cv_use_default_link + fi fi { $as_echo "$as_me:${as_lineno-$LINENO}: checking linker output format" >&5 diff --git a/configure.in b/configure.in index a28cd70..65ace27 100644 --- a/configure.in +++ b/configure.in @@ -117,10 +117,9 @@ AC_ARG_WITH([headers], AC_SUBST(use_default_link) AC_ARG_WITH([default-link], AC_HELP_STRING([--with-default-link], - [do not use explicit linker scripts - @<:@default=no@:>@]), + [do not use explicit linker scripts]), [use_default_link=$withval], - [use_default_link=no]) + [use_default_link=default]) AC_ARG_ENABLE([sanity-checks], AC_HELP_STRING([--disable-sanity-checks], @@ -1801,6 +1800,59 @@ EOF fi rm -f conftest*]) AC_SUBST(libc_cv_hashstyle) + + # The linker's default -shared behavior is good enough if it + # does these things that our custom linker scripts ensure that + # all allocated NOTE sections come first. + if test "$use_default_link" = default; then + AC_CACHE_CHECK([for sufficient default -shared layout], + libc_cv_use_default_link, [dnl + libc_cv_use_default_link=no + cat > conftest.s <<\EOF + .section .note.a,"a",%note + .balign 4 + .long 4,4,9 + .string "GNU" + .string "foo" + .section .note.b,"a",%note + .balign 4 + .long 4,4,9 + .string "GNU" + .string "bar" +EOF + if AC_TRY_COMMAND([dnl + ${CC-cc} $ASFLAGS -shared -o conftest.so conftest.s 1>&AS_MESSAGE_LOG_FD]) && + ac_try=`$READELF -S conftest.so | sed -n \ + ['${x;p;} + s/^ *\[ *[1-9][0-9]*\] *\([^ ][^ ]*\) *\([^ ][^ ]*\) .*$/\2 \1/ + t a + b + : a + H']` + then + libc_seen_a=no libc_seen_b=no + set -- $ac_try + while test $# -ge 2 -a "$1" = NOTE; do + case "$2" in + .note.a) libc_seen_a=yes ;; + .note.b) libc_seen_b=yes ;; + esac + shift 2 + done + case "$libc_seen_a$libc_seen_b" in + yesyes) + libc_cv_use_default_link=yes + ;; + *) + echo >&AS_MESSAGE_LOG_FD "\ +$libc_seen_a$libc_seen_b from: +$ac_try" + ;; + esac + fi + rm -f conftest*]) + use_default_link=$libc_cv_use_default_link + fi fi AC_CACHE_CHECK(linker output format, libc_cv_output_format, [dnl |