doc: teach doc/advanced_options about NIT_GC_OPTION

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/doc/advanced_options b/doc/advanced_options
index ae49003..814f81b 100644 (file)
--- a/doc/advanced_options
+++ b/doc/advanced_options
@@ -1,7 +1,5 @@
 * GC **************************************************************************
 
-If Bohem's GC is available, it will be automatically used within compiled NIT
-programs.
-
-On GC enabled NIT program, GC can be dynamically disabled if the NIT_NOGC envvar is set.
+Nit programs can dynamically select a GC at runtime. Just set NIT_GC_OPTION envvar.
+Set it to "help" to list available GC at the begin of the program.