diff --git a/libwps.spec b/libwps.spec
index adc0ad6..51ade2b 100644
--- a/libwps.spec
+++ b/libwps.spec
@@ -56,7 +56,7 @@ The %{name}-doc package contains documentation files for %{name}
 touch -r aclocal.m4 configure configure.in
 
 %build
-%configure --disable-static --disable-werror --with-sharedptr=c++11 CXXFLAGS=-std=c++11
+%configure --disable-static --disable-werror --with-sharedptr=c++11 CXXFLAGS="$CXXFLAGS -std=c++11"
 sed -i 's|^hardcode_libdir_flag_spec=.*|hardcode_libdir_flag_spec=""|g' libtool
 sed -i 's|^runpath_var=LD_RUN_PATH|runpath_var=DIE_RPATH_DIE|g' libtool
 make %{?_smp_mflags}