From: Tom Tromey <tromey@adacore.com>
Date: Fri, 1 Sep 2023 17:04:58 +0000 (-0600)
Subject: Fix latent bug in ser_windows_send_break
X-Git-Tag: binutils-2_42~821
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4dda9cc4b03788d1cf0416b39a3ab3780caf27fd;p=thirdparty%2Fbinutils-gdb.git

Fix latent bug in ser_windows_send_break

The ClearCommBreak documentation says:

    If the function fails, the return value is zero.

ser_windows_send_break inverts this check.  This has never been
noticed because the caller doesn't check the result.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30770
---

diff --git a/gdb/ser-mingw.c b/gdb/ser-mingw.c
index c0aa5d8d0b9..806f3999385 100644
--- a/gdb/ser-mingw.c
+++ b/gdb/ser-mingw.c
@@ -137,7 +137,7 @@ ser_windows_send_break (struct serial *scb)
   /* Delay for 250 milliseconds.  */
   Sleep (250);
 
-  if (ClearCommBreak (h))
+  if (ClearCommBreak (h) == 0)
     return -1;
 
   return 0;