Support multiple SRCDIR in INCLUDEDIR default

If multiple `SRCDIR`s are provided, the default `INCLUDEDIR` needs to
append `/includes` to each, not simply the last one.

diff --git a/GNUmakefile b/GNUmakefile
index 952aebd6f4d67ef5681072377004e94f65994832..5237a2d813d967577395424b23592a7495a638fa 100644 (file)
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -149,7 +149,7 @@ SRCDIR := sources
 # Multiple directories can be given so long as files with the same name do not exist in each.
 #
 # These can be inside of `SRCDIR´ directories if desired.
-INCLUDEDIR := $(SRCDIR)/includes
+INCLUDEDIR := $(foreach dir,$(SRCDIR),$(dir)/includes)
 
 # The directory in which to generate temporary buildfiles.
 #