New module 'arg-nonnull'. Declare which arguments expect non-NULL values.

modules/string

@@ -9,6 +9,7 @@ Depends-on:
 extensions
 include_next
 link-warning
+arg-nonnull
 stddef
 
 configure.ac:
@@ -19,7 +20,7 @@ BUILT_SOURCES += string.h
 
 # We need the following in order to create <string.h> when the system
 # doesn't have one that works with the given compiler.
-string.h: string.in.h $(LINK_WARNING_H)
+string.h: string.in.h $(LINK_WARNING_H) $(ARG_NONNULL_H)
 	$(AM_V_GEN)rm -f $@-t $@ && \
 	{ echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */' && \
 	  sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
@@ -86,6 +87,7 @@ string.h: string.in.h $(LINK_WARNING_H)
 	      -e 's|@''REPLACE_STRTOK_R''@|$(REPLACE_STRTOK_R)|g' \
 	      -e 's|@''UNDEFINE_STRTOK_R''@|$(UNDEFINE_STRTOK_R)|g' \
 	      -e '/definition of GL_LINK_WARNING/r $(LINK_WARNING_H)' \
+	      -e '/definition of _GL_ARG_NONNULL/r $(ARG_NONNULL_H)' \
 	      < $(srcdir)/string.in.h; \
 	} > $@-t && \
 	mv $@-t $@