preproc: fix potential bug regarding MMacro->prev and %rep

1 files changed, 1 insertions, 0 deletions

diff --git a/preproc.c b/preproc.c
index cf625c29..69c135de 100644
--- a/preproc.c
+++ b/preproc.c
@@ -2768,6 +2768,7 @@ static int do_directive(Token * tline)
 
         tmp_defining = defining;
         defining = nasm_malloc(sizeof(MMacro));
+		defining->prev = NULL;
         defining->name = NULL;  /* flags this macro as a %rep block */
         defining->casesense = false;
         defining->plus = false;