[PATCH v2] Modify gas uleb128 support test

[PATCH v2] Modify gas uleb128 support test

[mengqinggang]

Some assemblers (GNU as for LoongArch) generates relocations for leb128
symbol arithmetic for relaxation, we need to disable relaxation probing
leb128 support then.

gcc/ChangeLog:

    * configure: Regenerate.
    * configure.ac: Checking assembler for -mno-relax support.
    Disable relaxation when probing leb128 support.

co-authored-by: Xi Ruoyao <xry111@xry111.site>
---
 gcc/configure    | 35 ++++++++++++++++++++++++++++++++++-
 gcc/configure.ac | 10 +++++++++-
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/gcc/configure b/gcc/configure
index 07e8a64afbb..b1cc52a8041 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -24676,6 +24676,39 @@ _ACEOF
 
 
 
+# Some assemblers (GNU as for LoongArch) generates relocations for
+# leb128 symbol arithmetic for relaxation, we need to disable relaxation
+# probing leb128 support then.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for -mno-relax support" >&5
+$as_echo_n "checking assembler for -mno-relax support... " >&6; }
+if ${gcc_cv_as_mno_relax+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  gcc_cv_as_mno_relax=no
+  if test x$gcc_cv_as != x; then
+    $as_echo '.text' > conftest.s
+    if { ac_try='$gcc_cv_as $gcc_cv_as_flags -mno-relax -o conftest.o conftest.s >&5'
+  { { eval echo "\"\$as_me\":${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; }; }
+    then
+	gcc_cv_as_mno_relax=yes
+    else
+      echo "configure: failed program was" >&5
+      cat conftest.s >&5
+    fi
+    rm -f conftest.o conftest.s
+  fi
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_as_mno_relax" >&5
+$as_echo "$gcc_cv_as_mno_relax" >&6; }
+if test $gcc_cv_as_mno_relax = yes; then
+  check_leb128_asflags=-mno-relax
+fi
+
+
 # Check if we have .[us]leb128, and support symbol arithmetic with it.
 # Older versions of GAS and some non-GNU assemblers, have a bugs handling
 # these directives, even when they appear to accept them.
@@ -24694,7 +24727,7 @@ L1:
 L2:
 	.uleb128 0x8000000000000000
 ' > conftest.s
-    if { ac_try='$gcc_cv_as $gcc_cv_as_flags  -o conftest.o conftest.s >&5'
+    if { ac_try='$gcc_cv_as $gcc_cv_as_flags $check_leb128_asflags -o conftest.o conftest.s >&5'
   { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
   (eval $ac_try) 2>&5
   ac_status=$?
diff --git a/gcc/configure.ac b/gcc/configure.ac
index cb4be11facd..10027a4aaaa 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -3229,10 +3229,18 @@ AC_MSG_RESULT($gcc_cv_ld_ro_rw_mix)
 
 gcc_AC_INITFINI_ARRAY
 
+# Some assemblers (GNU as for LoongArch) generates relocations for
+# leb128 symbol arithmetic for relaxation, we need to disable relaxation
+# probing leb128 support then.
+gcc_GAS_CHECK_FEATURE([-mno-relax support],
+  gcc_cv_as_mno_relax,[-mno-relax],[.text],,
+  [check_leb128_asflags=-mno-relax])
+
 # Check if we have .[us]leb128, and support symbol arithmetic with it.
 # Older versions of GAS and some non-GNU assemblers, have a bugs handling
 # these directives, even when they appear to accept them.
-gcc_GAS_CHECK_FEATURE([.sleb128 and .uleb128], gcc_cv_as_leb128,,
+gcc_GAS_CHECK_FEATURE([.sleb128 and .uleb128], gcc_cv_as_leb128,
+[$check_leb128_asflags],
 [	.data
 	.uleb128 L2 - L1
 L1:
-- 
2.36.0

Re: [PATCH v2] Modify gas uleb128 support test

[chenglulu]

在 2023/9/15 下午12:04, mengqinggang 写道:
> diff --git a/gcc/configure.ac b/gcc/configure.ac
> index cb4be11facd..10027a4aaaa 100644
> --- a/gcc/configure.ac
> +++ b/gcc/configure.ac
> @@ -3229,10 +3229,18 @@ AC_MSG_RESULT($gcc_cv_ld_ro_rw_mix)
>   
>   gcc_AC_INITFINI_ARRAY
>   
> +# Some assemblers (GNU as for LoongArch) generates relocations for
> +# leb128 symbol arithmetic for relaxation, we need to disable relaxation
> +# probing leb128 support then.
> +gcc_GAS_CHECK_FEATURE([-mno-relax support],
> +  gcc_cv_as_mno_relax,[-mno-relax],[.text],,
> +  [check_leb128_asflags=-mno-relax])
> +

Hi, RuoYao:

Do we need to add architectural distinction here?