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diff --git a/libraries/Makefile b/libraries/Makefile
index 0ef78d8..85fbc77 100644 (file)
--- a/libraries/Makefile
+++ b/libraries/Makefile
@@ -168,6 +168,8 @@ endif
 $(foreach SUBDIR,$(SUBDIRS),rebuild.library.$(SUBDIR)):\
 rebuild.library.%: clean.library.% make.library.%
 
+# NB. we're depending on make chasing dependencies from left to right here.
+# This bit goes wrong with 'make -j'.
 build: $(foreach SUBDIR,$(SUBDIRS),make.library.$(SUBDIR))
 build: installPackage/installPackage