diff --git a/GNUmakefiles/CLibrary b/GNUmakefiles/CLibrary
index 50364c52a2dc666c0750b8b013a5ba1431b377b9..f76d9688a2ee916e6a29e0d17801724dc5ec5d01 100644
--- a/GNUmakefiles/CLibrary
+++ b/GNUmakefiles/CLibrary
@@ -25,6 +25,7 @@ INCLUDED_CLIBRARY = YES
 # DIRS         (opt) (stamp object for directory creation - otherwise _dirs)
 # HDRS         (opt) (header files to export, no h. prefix - otherwise ${TARGET})
 # ASMHDRS      (opt) (assembly header files to export, no Hdr. prefix - otherwise none)
+# EXPORTS      (opt) (dependencies for export_hdrs phase - otherwise deduced from ${HDRS} and ${ASMHDRS})
 # OBJS               (object files, no o. or oz. prefixes)
 # DBG_OBJS     (opt) (debug build object files, no o. or oz. prefixes - otherwise ${OBJS})
 # APP_OBJS     (opt) (release application object files, no o. or oz. prefixes - otherwise ${OBJS})
@@ -96,6 +97,7 @@ MOD_DBG_OBJS_ = $(addsuffix .odz,${MOD_DBG_OBJS})
 
 EXPORTING_HDRS    = $(addsuffix .exphdr,${HDRS})
 EXPORTING_ASMHDRS = $(addsuffix .expasm,${ASMHDRS})
+EXPORTS          ?= ${EXPORTING_HDRS} ${EXPORTING_ASMHDRS}
 EXPORTING_LIBS    = $(addsuffix .explib,${LIBRARIES})
 TARGET_LIBS       = $(addsuffix .${LIBEXT},${LIBRARIES})
 
@@ -185,7 +187,7 @@ create_exp_lib_dir:
 .Hdr.expasm:;       ${CP} $< ${EXPDIR}/$* ${CPFLAGS}
 .${LIBEXT}.explib:; ${CP} $< ${EXPDIR}/$< ${CPFLAGS}
 
-export_hdrs: create_exp_hdr_dirs ${DIRS} ${EXPORTING_ASMHDRS} ${EXPORTING_HDRS}
+export_hdrs: create_exp_hdr_dirs ${DIRS} ${EXPORTS}
 	[ ! -f ../VersionNum ] || ${CP} ../VersionNum ${EXPDIR}/LibVersion ${CPFLAGS}
 	@${ECHO} ${COMPONENT}: header export complete
 
diff --git a/Makefiles/CLibrary b/Makefiles/CLibrary
index 3b164c288836550a81a28ca173570879a3839edb..0adbafc0c7cd87003838a5f84b4d4daf6881a1b7 100644
--- a/Makefiles/CLibrary
+++ b/Makefiles/CLibrary
@@ -41,6 +41,7 @@ INCLUDED_CLIBRARY = YES
 # DIRS         (opt) (stamp object for directory creation - otherwise o._dirs)
 # HDRS         (opt) (header files to export, no h. prefix - otherwise ${TARGET})
 # ASMHDRS      (opt) (assembly header files to export, no Hdr. prefix - otherwise none)
+# EXPORTS      (opt) (dependencies for export_hdrs phase - otherwise deduced from ${HDRS} and ${ASMHDRS})
 # OBJS               (object files, no o. or oz. prefixes)
 # DBG_OBJS     (opt) (debug build object files, no o. or oz. prefixes - otherwise ${OBJS})
 # APP_OBJS     (opt) (release application object files, no o. or oz. prefixes - otherwise ${OBJS})
@@ -111,6 +112,7 @@ MOD_DBG_OBJS_ = $(addprefix odz.,${MOD_DBG_OBJS})
 
 EXPORTING_HDRS    = $(addprefix exphdr.,${HDRS})
 EXPORTING_ASMHDRS = $(addprefix expasm.,${ASMHDRS})
+EXPORTS          ?= ${EXPORTING_ASMHDRS} ${EXPORTING_HDRS}
 EXPORTING_LIBS    = $(addprefix explib.,${LIBRARIES})
 TARGET_LIBS       = $(addprefix ${LIBEXT}.,${LIBRARIES})
 
@@ -173,7 +175,7 @@ create_exp_lib_dir:
 .Hdr.expasm:;       ${CP} $< ${EXPDIR}.$< ${CPFLAGS}
 .${LIBEXT}.explib:; ${CP} $< ${EXPDIR}.$< ${CPFLAGS}
 
-export_hdrs: ${EXPORTING_ASMHDRS} ${EXPORTING_HDRS} ${DIRS} create_exp_hdr_dirs
+export_hdrs: ${EXPORTS} ${DIRS} create_exp_hdr_dirs
         @IfThere VersionNum then ${ECHO} ${CP} VersionNum ${EXPDIR}.LibVersion ${CPFLAGS}
         @IfThere VersionNum then ${CP} VersionNum ${EXPDIR}.LibVersion ${CPFLAGS}
         @IfThere ${EXPDIR}.h.*   then else ${RM} ${EXPDIR}.h