1 files changed, 3 insertions, 0 deletions
diff --git a/INSTALL b/INSTALL
index 10e53ff..982d5a7 100644
--- a/INSTALL
+++ b/INSTALL
@@ -233,6 +233,9 @@ options are passed to them:
     The command for invoking the builder, that is GPRbuild or Gnatmake.
     Default: gprbuild
 
+ GNATPREPFLAGS
+    A space-separated list of options to be passed to Gnatprep.
+
  GNATFLAGS
     A space-separated list with all of the optional parameters to be passed to
     the builder, including any options to be forwarded to the compiler, binder