-$(SPHINX_HTML_TARGET): $(SPHINX_SRC)
- $(LOCAL_SPHINXBUILD) -b html -E $(SPHINX_SOURCE_DIR) $(SPHINX_BUILD_HTML_DIR)
+# `PATH` is used as a replacement for `LD_LIBRARY_PATH` on Windows
+# builds (Cygwin, MinGW).
+#
+# `DYLD_LIBRARY_PATH` is used a replacement for `LD_LIBRARY_PATH` on
+# macOS builds.
+SPHINXBUILD = PATH="$(LLP):$$PATH" PYTHONPATH="$(PP):$(SPHINX_EXT_DIR)" LD_LIBRARY_PATH="$(LLP)" DYLD_LIBRARY_PATH="$(LLP)" $(PYTHON) -m sphinx
+SPHINX_SRC = \
+ $(SPHINX_SOURCE_DIR)/common.rst \
+ $(SPHINX_SOURCE_DIR)/index.rst \
+ $(SPHINX_SOURCE_DIR)/installation.rst \
+ $(SPHINX_SOURCE_DIR)/examples.rst