[gnumeric] fix tooltips (#647240)

[Andreas J. Guelzow <guelzow src gnome org>]

commit 794beae7325570e01ce657ae40a6d485e04adb07
Author: Andreas J Guelzow <aguelzow pyrshep ca>
Date:   Fri Apr 8 21:19:41 2011 -0600

    fix tooltips (#647240)
    
    2011-04-08  Andreas J. Guelzow <aguelzow pyrshep ca>
    
    	* src/func.c (gnm_func_get_arg_description): fix zero-based index
    	counting, fixes #647240

 ChangeLog  |    5 +++++
 src/func.c |    2 +-
 2 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index bb77813..aa2a74f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2011-04-08  Andreas J. Guelzow <aguelzow pyrshep ca>
+
+	* src/func.c (gnm_func_get_arg_description): fix zero-based index 
+	counting, fixes #647240
+	
 2011-04-02  Andreas J. Guelzow <aguelzow pyrshep ca>
 
 	* src/sheet.c (sheet_range_contains_region): formulas ->formul\303\246
diff --git a/src/func.c b/src/func.c
index 31d0d22..7978a98 100644
--- a/src/func.c
+++ b/src/func.c
@@ -1429,7 +1429,7 @@ gnm_func_get_arg_description (GnmFunc const *fn_def, guint arg_idx)
 
 		if (fn_def->help[i].type != GNM_FUNC_HELP_ARG)
 			continue;
-		if (--arg_idx)
+		if (arg_idx--)
 			continue;
 
 		desc = strchr (F2 (fn_def, fn_def->help[i].text), ':');