Fix install when various DOC variables are empty

diff --git a/ghc.mk b/ghc.mk
index cb00064..f345405 100644 (file)
--- a/ghc.mk
+++ b/ghc.mk
@@ -797,18 +797,24 @@ install_headers: $(INSTALL_HEADERS)
 
 install_docs: $(INSTALL_HEADERS)
        $(INSTALL_DIR) $(DESTDIR)$(docdir)
+ifneq "$(INSTALL_DOCS)" ""
        for i in $(INSTALL_DOCS); do \
                $(INSTALL_DOC) $(INSTALL_OPTS) $$i $(DESTDIR)$(docdir); \
        done
-       $(INSTALL_DIR) $(INSTALL_OPTS) $(DESTDIR)$(docdir)/html; \
-       $(INSTALL_DOC) $(INSTALL_OPTS) docs/index.html $(DESTDIR)$(docdir)/html; \
+endif
+       $(INSTALL_DIR) $(INSTALL_OPTS) $(DESTDIR)$(docdir)/html
+       $(INSTALL_DOC) $(INSTALL_OPTS) docs/index.html $(DESTDIR)$(docdir)/html
+ifneq "$(INSTALL_LIBRARY_DOCS)" ""
        for i in $(INSTALL_LIBRARY_DOCS); do \
                $(INSTALL_DOC) $(INSTALL_OPTS) $$i $(DESTDIR)$(docdir)/html/libraries/; \
        done
+endif
+ifneq "$(INSTALL_HTML_DOC_DIRS)" ""
        for i in $(INSTALL_HTML_DOC_DIRS); do \
                $(INSTALL_DIR) $(INSTALL_OPTS) $(DESTDIR)$(docdir)/html/`basename $$i`; \
                $(INSTALL_DOC) $(INSTALL_OPTS) $$i/* $(DESTDIR)$(docdir)/html/`basename $$i`; \
        done
+endif
 
 INSTALLED_PACKAGE_CONF=$(DESTDIR)$(topdir)/package.conf.d