Disable -Werror (Fix F26FTBFS, RHBZ#1424580).

Force USE_CPP14 on fedora >=26.
Prevent CMakeList.txt from overiding -std=...

OpenImageIO.spec

@@ -3,7 +3,7 @@
 
 Name:           OpenImageIO
 Version:        1.7.10
-Release:        4%{?dist}
+Release:        5%{?dist}
 Summary:        Library for reading and writing images
 
 Group:          Development/Libraries
@@ -113,6 +113,10 @@ rm -rf src/include/tbb
 #rm -rf ../oiio-images && mkdir ../oiio-images && pushd ../oiio-images
 #tar --strip-components=1 -xzf %{SOURCE1}
 
+# Do not override -std= !!!
+sed -i \
+-e 's,^\([ ]\+add_definitions.*-std=c++1.*\)$,# \1,' \
+CMakeLists.txt
 
 %build
 rm -rf build/linux && mkdir -p build/linux && pushd build/linux
@@ -126,11 +130,14 @@ rm -rf build/linux && mkdir -p build/linux && pushd build/linux
        -DINSTALL_FONTS:BOOL=FALSE \
        -DUSE_EXTERNAL_PUGIXML:BOOL=TRUE \
        -DUSE_OPENSSL:BOOL=TRUE \
+       -DSTOP_ON_WARNING:BOOL=FALSE \
+%if 0%{?fedora} >= 26
+       -DUSE_CPP14:BOOL=TRUE \
+%endif
 %ifarch ppc ppc64
        -DNOTHREADS:BOOL=FALSE \
 %endif
        -DVERBOSE=TRUE \
-       -DSTOP_ON_WARNING=FALSE \
        ../../
 
 make %{?_smp_mflags}
@@ -181,6 +188,11 @@ cp -a src/doc/*.1 %{buildroot}%{_mandir}/man1
 
 
 %changelog
+* Sun Feb 19 2017 Ralf Corsépius <corsepiu@fedoraproject.org> - 1.7.10-5
+- Disable -Werror (Fix F26FTBFS, RHBZ#1424580).
+- Force USE_CPP14 on fedora >=26.
+- Prevent CMakeList.txt from overiding -std=...
+
 * Fri Feb 17 2017 Richard Shaw <hobbes1069@gmail.com> - 1.7.10-4
 - Rebuild for boost 1.63