[glibc] LoongArch: Use medium cmodel build libc_nonshared.a.

[glibc] LoongArch: Use medium cmodel build libc_nonshared.a.

[Yinyu Cai]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=9f482b73f41a9a1bbfb173aad0733d1c824c788a

commit 9f482b73f41a9a1bbfb173aad0733d1c824c788a
Author: Chenghua Xu <xuchenghua@loongson.cn>
Date:   Wed Sep 7 10:33:00 2022 +0800

    LoongArch: Use medium cmodel build libc_nonshared.a.
    
    This patch is used to fix address out-of-bounds error when building
    Chrome.

Diff:
---
 sysdeps/loongarch/Makefile     |  6 ++++++
 sysdeps/loongarch/configure    | 22 ++++++++++++++++++++++
 sysdeps/loongarch/configure.ac | 10 ++++++++++
 3 files changed, 38 insertions(+)

diff --git a/sysdeps/loongarch/Makefile b/sysdeps/loongarch/Makefile
index 746d4c2c8f..1778fd1c88 100644
--- a/sysdeps/loongarch/Makefile
+++ b/sysdeps/loongarch/Makefile
@@ -5,3 +5,9 @@ endif
 # LoongArch's assembler also needs to know about PIC as it changes the
 # definition of some assembler macros.
 ASFLAGS-.os += $(pic-ccflag)
+
+# All the objects in lib*_nonshared.a need to be compiled with medium code
+# model or large applications may fail to link.
+ifeq (yes,$(have-cmodel-medium))
+CFLAGS-.oS += -mcmodel=medium
+endif
diff --git a/sysdeps/loongarch/configure b/sysdeps/loongarch/configure
index 3046915ce2..a08ba67c9a 100644
--- a/sysdeps/loongarch/configure
+++ b/sysdeps/loongarch/configure
@@ -72,3 +72,25 @@ if test "$libc_cv_static_pie_on_loongarch" = yes; then
   $as_echo "#define SUPPORT_STATIC_PIE 1" >>confdefs.h
 
 fi
+
+  # Check if gcc supports option -mcmodel=medium.
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CC supports option -mcmodel=medium" >&5
+$as_echo_n "checking whether $CC supports option -mcmodel=medium... " >&6; }
+if ${libc_cv_loongarch_cmodel_medium+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+    if { ac_try='${CC-cc} -c $CFLAGS -mcmodel=medium /dev/null 1>&5'
+  { { eval echo "\"\$as_me\":${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; }; }; then
+    libc_cv_loongarch_cmodel_medium=yes
+  else
+    libc_cv_loongarch_cmodel_medium=no
+  fi
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_loongarch_cmodel_medium" >&5
+$as_echo "$libc_cv_loongarch_cmodel_medium" >&6; }
+config_vars="$config_vars
+have-cmodel-medium = $libc_cv_loongarch_cmodel_medium"
diff --git a/sysdeps/loongarch/configure.ac b/sysdeps/loongarch/configure.ac
index 06dd408ad9..9df387f086 100644
--- a/sysdeps/loongarch/configure.ac
+++ b/sysdeps/loongarch/configure.ac
@@ -51,3 +51,13 @@ EOF
 if test "$libc_cv_static_pie_on_loongarch" = yes; then
   AC_DEFINE(SUPPORT_STATIC_PIE)
 fi
+
+  # Check if gcc supports option -mcmodel=medium.
+AC_CACHE_CHECK(whether $CC supports option -mcmodel=medium,
+	       libc_cv_loongarch_cmodel_medium, [
+  if AC_TRY_COMMAND(${CC-cc} -c $CFLAGS -mcmodel=medium /dev/null 1>&AS_MESSAGE_LOG_FD); then
+    libc_cv_loongarch_cmodel_medium=yes
+  else
+    libc_cv_loongarch_cmodel_medium=no
+  fi])
+LIBC_CONFIG_VAR([have-cmodel-medium], [$libc_cv_loongarch_cmodel_medium])