fix compile error in openeuler:23.09: use c++14 standard

(cherry picked from commit 9b371e678ce10b07b786a0b97e739afef2e76882)

libcutl.spec

@@ -3,7 +3,7 @@
 
 Name:           libcutl
 Version:        %{base_version}.0
-Release:        17
+Release:        18
 Summary:        C++ utility library from Code Synthesis
 License:        MIT and BSL-1.0
 URL:            http://www.codesynthesis.com/projects/libcutl/
@@ -48,6 +48,8 @@ rm -rv cutl/details/boost
 rm -rv cutl/details/expat
 
 %build
+CC="$CC -std=gnu89"
+export CXXFLAGS="-std=c++14 $RPM_OPT_FLAGS"
 # Use the system Boost and expat libraries
 confopts="--disable-static --with-external-expat %{?external_boost}"
 # If building on RHEL 5
@@ -76,6 +78,9 @@ rm -rf $RPM_BUILD_ROOT%{_datadir}
 %{_libdir}/pkgconfig/libcutl.pc
 
 %changelog
+* Fri Aug 18 2023 wangjunqi <wangjunqi@kylinos.cn> - 1.10.0-18
+- fix compile error in openeuler:23.09: use c++14 standard
+
 * Tue Oct 08 2019 Antonio Trande <sagitter@fedoraproject.org> - 1.10.0-17
 - Some minor fixes