From 0471e845e4d121e5551fb851a1854b963b3b1a96 Mon Sep 17 00:00:00 2001
From: Marc Mutz <marc.mutz@qt.io>
Date: Thu, 18 Jul 2024 14:03:39 +0200
Subject: [PATCH] qtesttostring.h: don't write 32..256B of NULs

qsnprint() is unconditionally called to fill the buffer and is
guaranteed to NUL-terminate, so there's no point in filling the whole
stack buffer with NULs beforehand. Leave it uninitialized.

The code was moved in 4ae6f40b3a2e2fe4f617a1c911c8d066c18cdab9, so not
picking further than that.

Change-Id: I34d456ebd2990aa242ccc42693adbbf1f64148de
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 4c5b437a3ce84354dfa3bf2c4706e05144ac03a3)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/testlib/qtesttostring.h | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/testlib/qtesttostring.h b/src/testlib/qtesttostring.h
index d5d48bb4f4e..903392697d6 100644
--- a/src/testlib/qtesttostring.h
+++ b/src/testlib/qtesttostring.h
@@ -195,7 +195,7 @@ template<> inline char *toString(const QChar &c)
 {
     const ushort uc = c.unicode();
     if (uc < 128) {
-        char msg[32] = {'\0'};
+        char msg[32];
         qsnprintf(msg, sizeof(msg), "QChar: '%c' (0x%x)", char(uc), unsigned(uc));
         return qstrdup(msg);
     }
@@ -213,21 +213,21 @@ template<> inline char *toString(const QModelIndex &idx)
 
 template<> inline char *toString(const QPoint &p)
 {
-    char msg[128] = {'\0'};
+    char msg[128];
     qsnprintf(msg, sizeof(msg), "QPoint(%d,%d)", p.x(), p.y());
     return qstrdup(msg);
 }
 
 template<> inline char *toString(const QSize &s)
 {
-    char msg[128] = {'\0'};
+    char msg[128];
     qsnprintf(msg, sizeof(msg), "QSize(%dx%d)", s.width(), s.height());
     return qstrdup(msg);
 }
 
 template<> inline char *toString(const QRect &s)
 {
-    char msg[256] = {'\0'};
+    char msg[256];
     qsnprintf(msg, sizeof(msg), "QRect(%d,%d %dx%d) (bottomright %d,%d)",
               s.left(), s.top(), s.width(), s.height(), s.right(), s.bottom());
     return qstrdup(msg);
@@ -235,21 +235,21 @@ template<> inline char *toString(const QRect &s)
 
 template<> inline char *toString(const QPointF &p)
 {
-    char msg[64] = {'\0'};
+    char msg[64];
     qsnprintf(msg, sizeof(msg), "QPointF(%g,%g)", p.x(), p.y());
     return qstrdup(msg);
 }
 
 template<> inline char *toString(const QSizeF &s)
 {
-    char msg[64] = {'\0'};
+    char msg[64];
     qsnprintf(msg, sizeof(msg), "QSizeF(%gx%g)", s.width(), s.height());
     return qstrdup(msg);
 }
 
 template<> inline char *toString(const QRectF &s)
 {
-    char msg[256] = {'\0'};
+    char msg[256];
     qsnprintf(msg, sizeof(msg), "QRectF(%g,%g %gx%g) (bottomright %g,%g)",
               s.left(), s.top(), s.width(), s.height(), s.right(), s.bottom());
     return qstrdup(msg);