do it correctly this time

setup.py

@@ -56,6 +56,11 @@ class CMakeBuild(build_ext):
             if not cmake_generator:
                 cmake_args += ["-GNinja"]
 
+            # If this is a CI build, make sure not to use any advanced CPU features
+            if bool(os.environ.get('CI', False)):
+                print('forcing use of base x86_64 instruction set for CI build')
+                cmake_args += ['-DCMAKE_CXX_FLAGS=-mtune=x86_64']
+
         else:
             # Single config generators are handled "normally"
             single_config = any(x in cmake_generator for x in {"NMake", "Ninja"})
@@ -84,11 +89,6 @@ class CMakeBuild(build_ext):
                 ]
                 build_args += ["--config", cfg]
 
-            # If this is a CI build, make sure not to use any advanced CPU features
-            if bool(os.environ.get('CI', False)):
-                cmake_args += ['-DCMAKE_CXX_FLAGS=-mtune=x86_64']
-                build_args += ['-DCMAKE_VERBOSE_MAKEFILE:BOOL=ON']
-
         # Set CMAKE_BUILD_PARALLEL_LEVEL to control the parallel build level
         # across all generators.
         if "CMAKE_BUILD_PARALLEL_LEVEL" not in os.environ: