do not write null sha1s to on-disk index

diff --git a/prompt.h b/prompt.h
index 9ab85a78a24db86283f22168db61e51d5ef87546..04f321a781d37af780b906c2a4564c08eea830c8 100644 (file)
--- a/prompt.h
+++ b/prompt.h
@@ -2,6 +2,7 @@
 #define PROMPT_H
 
 #define PROMPT_ASKPASS (1<<0)
+#define PROMPT_ECHO    (1<<1)
 
 char *git_prompt(const char *prompt, int flags);
 char *git_getpass(const char *prompt);