diff -up src/module_list.py.orig src/module_list.py
--- src/module_list.py.orig	2019-06-27 11:30:20.794201914 -0600
+++ src/module_list.py	2019-06-27 11:38:23.103196674 -0600
@@ -514,7 +514,7 @@ ext_modules = [
     Extension('sage.libs.lcalc.lcalc_Lfunction',
               sources = ['sage/libs/lcalc/lcalc_Lfunction.pyx'],
               libraries = ['m', 'ntl', 'Lfunction'],
-              extra_compile_args=["-O3", "-ffast-math"],
+              extra_compile_args=["-std=gnu++11", "-ffast-math"],
               language = 'c++'),
 
     Extension('sage.libs.libecm',