diff --git a/glibc.spec b/glibc.spec
index 80b4988..8fe474c 100644
--- a/glibc.spec
+++ b/glibc.spec
@@ -83,8 +83,8 @@
 %endif
 
 Name:          glibc
-Version:       2.30
-Release:       6mamba
+Version:       2.31
+Release:       1mamba
 Summary:       The GNU libc libraries
 Group:         System/Libraries
 Vendor:        openmamba
@@ -147,12 +147,6 @@ Requires:      ldconfig = %{?epoch:%epoch:}%{version}-%{release}
 Requires:      locales = %{?epoch:%epoch:}%{version}-%{release}
 Requires:      glibc-utils = %{?epoch:%epoch:}%{version}-%{release}
 %systemd_requires
-%ifarch x86_64
-Provides:      glibc-multilib
-Obsoletes:     glibc-multilib
-Obsoletes:     glibc.i586
-%endif
-Prefix:        %{_prefix}
 BuildRoot:     %{_tmppath}/%{name}-%{version}-root
 
 # FIXME :
@@ -170,11 +164,7 @@ The glibc package also contains national language (locale) support.
 Summary:       Header and object files for development using standard C libraries.
 Group:         Development/Libraries
 Requires:      %{name} = %{?epoch:%epoch:}%{version}-%{release}
-Prereq:        %{__install_info}
-%ifarch x86_64
-Provides:      glibc-multilib-devel
-Obsoletes:     glibc-multilib-devel
-%endif
+Requires(pre): %{__install_info}
 
 %description devel
 The glibc-devel package contains the header and object files necessary for developing programs which use the standard C libraries (which are used by nearly all programs).
@@ -186,15 +176,38 @@ The header files are also needed for rebuilding the kernel.
 
 Install glibc-devel if you are going to develop programs which will use the standard C libraries.
 
+%package multilib
+Summary:        GNU libc multilib (lib32) libraries
+Group:          System/Libraries
+Provides:       glibc-multilib-i18ndata
+Obsoletes:      glibc-multilib-i18ndata
+Provides:       glibc-multilib-utils
+Obsoletes:      glibc-multilib-utils
+
+%description multilib
+The glibc package contains standard libraries which are used by multiple programs on the system.
+In order to save disk space and memory, as well as to make upgrading easier, common system code is kept in one place and shared between programs.
+This particular package contains the most important sets of shared libraries: the standard C library and the standard math library. Without these two libraries, a Linux system will not function.
+The glibc-multilib package provides lib32 libraries for 32-bit build support on x86_64 arch.
+
+%package multilib-devel
+Summary:        GNU libc multilib (lib32) libraries and files for development
+Group:          Development/Libraries
+Requires:       glibc-multilib =  %{?epoch:%epoch:}%{version}-%{release}
+Provides:       glibc-multilib-apidocs
+Obsoletes:      glibc-multilib-apidocs
+
+%description multilib-devel
+The glibc package contains standard libraries which are used by multiple programs on the system.
+In order to save disk space and memory, as well as to make upgrading easier, common system code is kept in one place and shared between programs.
+This particular package contains the most important sets of shared libraries: the standard C library and the standard math library. Without these two libraries, a Linux system will not function.
+The glibc-multilib-devel package provides lib32 libbraries and other files for development for 32-bit build support on x86_64 arch.
+
 %if %{build_doc}
 %package apidocs
 Summary:        GNU libc libraries API documentation
 Group:          Documentation
 Requires:       glibc-devel =  %{?epoch:%epoch:}%{version}-%{release}
-%ifarch x86_64
-Provides:      glibc-multilib-apidocs
-Obsoletes:     glibc-multilib-apidocs
-%endif
 
 %description apidocs
 GNU libc libraries API documentation.
@@ -204,10 +217,6 @@ GNU libc libraries API documentation.
 Summary:       Database sources for 'locale'
 Group:         System/Libraries
 Requires(pre): %{name} = %{?epoch:%epoch:}%{version}-%{release}
-%ifarch x86_64
-Provides:      glibc-multilib-i18ndata
-Obsoletes:     glibc-multilib-i18ndata
-%endif
 
 %description i18ndata
 This package contains the data needed to build the locale data files to use the internationalization features of the GNU libc.
@@ -216,10 +225,6 @@ This package contains the data needed to build the locale data files to use the
 Summary:       Development utilities from GNU C library
 Group:         Development/Tools
 Requires:      %{name} = %{?epoch:%epoch:}%{version}-%{release}
-%ifarch x86_64
-Provides:      glibc-multilib-utils
-Obsoletes:     glibc-multilib-utils
-%endif
 
 %description utils
 The glibc-utils package contains memusage, a memory usage profiler, mtrace, a memory leak tracer and, a function call tracer which can be helpful during program debugging.
@@ -312,7 +317,17 @@ ln -sf %{_includedir}/sys/capability.h include/sys/capability.h
 # create find-provides and find-requires script in order to ignore GLIBC_PRIVATE errors
 cat > find_provides.sh << _EOF
 #! /bin/sh
+%if "%{_target_platform}" == "%{_host}"
+%if "%{?stage1}" != "1"
+# set again +x on libraries for which strip has been disabled in %install
+#chmod -x %{buildroot}/%{slibdir}/ld-*.so
+#chmod -x %{buildroot}/%{slibdir}/libc-*.so
+chmod +x %{buildroot}/%{slibdir}/libpthread-*.so
+chmod +x %{buildroot}/%{slibdir}/libthread_db-*.so
+%endif
+%endif
 %{_prefix}/lib/rpm/find-provides | grep -v GLIBC_PRIVATE
+# work around to avoid stripping libthread_db-1.0.so for debugging
 exit 0
 _EOF
 chmod +x find_provides.sh
@@ -329,17 +344,17 @@ chmod +x find_requires.sh
 case %{target_cpu} in
    i*86|athlon*)
      platform_includes=asm-x86
-     buildflags="-mtune=pentiumpro -g -O3"
+     buildflags="-mtune=pentiumpro -g -O2"
      CONFIG_OPTS="--enable-targets=i586-%{_target_vendor}-linux --enable-cet"
    ;;
    ppc|powerpc)
      platform_includes=asm-powerpc
-     buildflags="-g -O3"
+     buildflags="-g -O2"
      CONFIG_OPTS="--enable-targets=powerpc64-%{_target_vendor}-linux"
    ;;
    arm)
      platform_includes=asm-arm
-     buildflags="-g -O3"
+     buildflags="-g -O2"
      %if "%{?softfloat}" == "1"
        CONFIG_LIBDIR_ADD="/soft-float"
        CONFIG_ADD="--without-fp"
@@ -354,7 +369,7 @@ case %{target_cpu} in
      ;;
    x86_64)
      platform_includes=asm-x86_64
-     buildflags="-g -O3"
+     buildflags="-g -O2"
      CONFIG_OPTS="--enable-targets=x86_64-%{_target_vendor}-linux --enable-multi-arch --enable-static-pie --enable-cet"
      ;;
    *)
@@ -426,13 +441,17 @@ rm -rf ../glibc-build
 mkdir ../glibc-build
 cd ../glibc-build
 
-#CFLAGS="$buildflags -Wl,--build-id"
+export CFLAGS="$buildflags"
+export CXXFLAGS="$buildflags"
 
 ../%{name}-%{version}/configure \
    ${_configure_flags[@]}
 
 %if "%{?stage1}" != "1"
-make %{_smp_mflags} -r %PARALLELMFLAGS=-s slibdir=%{slibdir} \
+# build libraries with fortify disabled
+echo "build-programs=no" >> configparms
+
+make %{_smp_mflags} -r %PARALLELMFLAGS=-s -j1 slibdir=%{slibdir} \
 %if "%{_target_platform}" != "%{_host}"
 %if "%{?stage2}" != "1"
   LDLIBS-resolv.so+="-lssp" LDFLAGS-nscd+="-lssp"
@@ -441,6 +460,12 @@ make %{_smp_mflags} -r %PARALLELMFLAGS=-s slibdir=%{slibdir} \
 %endif
 %endif
 
+# re-enable fortify for programs
+sed -i "/build-programs=/s#no#yes#" configparms
+echo "CC += -D_FORTIFY_SOURCE=2" >> configparms
+echo "CXX += -D_FORTIFY_SOURCE=2" >> configparms
+make %{_smp_mflags} -r %PARALLELMFLAGS=-s slibdir=%{slibdir}
+
 # build documentation (pdf and html formats)
 %if %{build_doc}
 make pdf html
@@ -566,10 +591,15 @@ rm -f %{buildroot}%{_localstatedir}/db/Makefile
 rm -f %{buildroot}%{_prefix}/%{_target_platform}/%{_sysconfdir}/ld.so.cache
 %endif
 
-## work around to avoid stripping libthread_db-1.0.so for debugging
-#%if "%{?stage1}" != "1"
-#chmod -x %{buildroot}/%{glibc_libdir}/libthread_db-1.0.so
-#%endif
+# work around to avoid stripping libthread_db-1.0.so for debugging
+%if "%{_target_platform}" == "%{_host}"
+%if "%{?stage1}" != "1"
+#chmod -x %{buildroot}/%{slibdir}/ld-*.so
+#chmod -x %{buildroot}/%{slibdir}/libc-*.so
+chmod -x %{buildroot}/%{slibdir}/libpthread-*.so
+chmod -x %{buildroot}/%{slibdir}/libthread_db-*.so
+%endif
+%endif
 
 rm -f %{buildroot}%{_libdir}/libnsl.*
 
@@ -693,7 +723,7 @@ fi
 %files
 %defattr(-,root,root)
 %config(noreplace) %{_sysconfdir}/rpc
-/%{slibdir}/*
+%attr(0755,-,-) /%{slibdir}/*
 %exclude %{slibdir}/libmemusage.so
 %exclude %{slibdir}/libpcprofile.so
 %dir %{glibc_libdir}/gconv
@@ -711,17 +741,6 @@ fi
 %{glibc_libexecdir}/getconf/POSIX_V6_LP64_OFF64
 %{glibc_libexecdir}/getconf/POSIX_V7_LP64_OFF64
 %{glibc_libexecdir}/getconf/XBS5_LP64_OFF64
-# Multilib
-%{_sysconfdir}/ld.so.conf.d/lib32-glibc.conf
-%{_prefix}/lib32/lib*-%{version}.so
-%{_prefix}/lib32/lib*.so.*
-%dir %{_prefix}/lib32/audit
-%{_prefix}/lib32/audit/sotruss-lib.so
-%{_prefix}/lib32/ld-%{version}.so
-%{_prefix}/lib32/ld-linux.so.*
-%dir %{_prefix}/lib32/gconv
-%{_prefix}/lib32/gconv/*
-%{_prefix}/lib32/locale
 %endif
 %doc COPYING* LICENSES
 
@@ -734,19 +753,32 @@ fi
 %if "%{build_profile}" == "1"
 %exclude %{glibc_libdir}/lib*_p.a
 %endif
+%{_infodir}/*
+%{_localstatedir}/db/Makefile
+%doc NEWS README*
+
 %ifarch x86_64
-# Multilib
+%files multilib
+%defattr(-,root,root)
+%{_sysconfdir}/ld.so.conf.d/lib32-glibc.conf
+%{_prefix}/lib32/lib*-%{version}.so
+%{_prefix}/lib32/lib*.so.*
+%dir %{_prefix}/lib32/audit
+%{_prefix}/lib32/audit/sotruss-lib.so
+%{_prefix}/lib32/ld-%{version}.so
+%{_prefix}/lib32/ld-linux.so.*
+%dir %{_prefix}/lib32/gconv
+%{_prefix}/lib32/gconv/*
+%{_prefix}/lib32/locale
+
+%files multilib-devel
+%defattr(-,root,root)
 %{_prefix}/lib32/*.o
 %{_prefix}/lib32/lib*.a
 %{_prefix}/lib32/lib*.so
 %exclude %{_prefix}/lib32/lib*-%{version}.so
 %endif
 
-%{_infodir}/*
-%{_localstatedir}/db/Makefile
-%doc ChangeLog
-%doc NEWS README*
-
 %if %{build_doc}
 %files apidocs
 %defattr(-,root,root)
@@ -841,6 +873,13 @@ fi
 %endif
 
 %changelog
+* Tue Mar 03 2020 Automatic Build System <autodist@mambasoft.it> 2.31-1mamba
+- automatic version update by autodist
+
+* Thu Dec 26 2019 Silvan Calarco <silvan.calarco@mambasoft.it> 2.30-7mamba
+- restore passing buildflags and don't strip libpthread-* and libthread_db-* for debugging
+- x86_64: restore glibc-multilib and glibc-multilib-devel subpackages since conflicts with glibc.i586 are resolved by using /usr/lib32
+
 * Tue Dec 10 2019 Silvan Calarco <silvan.calarco@mambasoft.it> 2.30-6mamba
 - install tmpfiles.d/nscd.conf