Issue #7518:  Move substitute definitions of C99 math functions from
pymath.c to Modules/_math.c.
diff --git a/setup.py b/setup.py
index bad88f7..f25b829 100644
--- a/setup.py
+++ b/setup.py
@@ -410,9 +410,9 @@
         # array objects
         exts.append( Extension('array', ['arraymodule.c']) )
         # complex math library functions
-        exts.append( Extension('cmath', ['cmathmodule.c'],
+        exts.append( Extension('cmath', ['cmathmodule.c', '_math.c'],
+                               depends=['_math.h'],
                                libraries=math_libs) )
-
         # math library functions, e.g. sin()
         exts.append( Extension('math',  ['mathmodule.c', '_math.c'],
                                depends=['_math.h'],