From 7e789b2998a9d6dc00ec99f89aadb43e96efb669 Mon Sep 17 00:00:00 2001
From: Axel Spoerl <axel.spoerl@qt.io>
Date: Mon, 22 Jan 2024 08:40:58 +0100
Subject: [PATCH] QFontEngine: Silence bogus gcc warnings

gcc warns about using uninitialized variables in
QFontEngine::getTrueTypeGlyphIndex. The warning is bogus, because all
variables subject to the warning are initialized by passing their
pointer to qSafeFromBigEndian().

Initialize them anyway to silence the warnings.

Pick-to: 6.5
Change-Id: I25e062f25e2b06701af5edca27a9e56b939daa79
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>
(cherry picked from commit e957ed97e0a7f6974db7d9f7ea52d94785464880)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit 9e8761e8e9755eb9dd7461682d47a6c64b39d5c0)
---
 src/gui/text/qfontengine.cpp | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp
index 5bfe8c00ee4..31a150e7b2f 100644
--- a/src/gui/text/qfontengine.cpp
+++ b/src/gui/text/qfontengine.cpp
@@ -1181,7 +1181,7 @@ const uchar *QFontEngine::getCMap(const uchar *table, uint tableSize, bool *isSy
     int tableToUse = -1;
     int score = Invalid;
     for (int n = 0; n < numTables; ++n) {
-        quint16 platformId;
+        quint16 platformId = 0;
         if (!qSafeFromBigEndian(maps + 8 * n, endPtr, &platformId))
             return nullptr;
 
@@ -1311,7 +1311,7 @@ resolveTable:
 quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint unicode)
 {
     const uchar *end = cmap + cmapSize;
-    quint16 format;
+    quint16 format = 0;
     if (!qSafeFromBigEndian(cmap, end, &format))
         return 0;
 
@@ -1328,7 +1328,7 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
         if (unicode >= 0xffff)
             return 0;
 
-        quint16 segCountX2;
+        quint16 segCountX2 = 0;
         if (!qSafeFromBigEndian(cmap + 6, end, &segCountX2))
             return 0;
 
@@ -1336,7 +1336,7 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
 
         int i = 0;
         for (; i < segCountX2/2; ++i) {
-            quint16 codePoint;
+            quint16 codePoint = 0;
             if (!qSafeFromBigEndian(ends + 2 * i, end, &codePoint))
                 return 0;
             if (codePoint >= unicode)
@@ -1345,7 +1345,7 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
 
         const unsigned char *idx = ends + segCountX2 + 2 + 2*i;
 
-        quint16 startIndex;
+        quint16 startIndex = 0;
         if (!qSafeFromBigEndian(idx, end, &startIndex))
             return 0;
         if (startIndex > unicode)
@@ -1353,20 +1353,20 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
 
         idx += segCountX2;
 
-        quint16 tmp;
+        quint16 tmp = 0;
         if (!qSafeFromBigEndian(idx, end, &tmp))
             return 0;
         qint16 idDelta = qint16(tmp);
 
         idx += segCountX2;
 
-        quint16 idRangeoffset_t;
+        quint16 idRangeoffset_t = 0;
         if (!qSafeFromBigEndian(idx, end, &idRangeoffset_t))
             return 0;
 
-        quint16 glyphIndex;
+        quint16 glyphIndex = 0;
         if (idRangeoffset_t) {
-            quint16 id;
+            quint16 id = 0;
             if (!qSafeFromBigEndian(idRangeoffset_t + 2 * (unicode - startIndex) + idx, end, &id))
                 return 0;
 
@@ -1379,17 +1379,17 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
         }
         return glyphIndex;
     } else if (format == 6) {
-        quint16 tableSize;
+        quint16 tableSize = 0;
         if (!qSafeFromBigEndian(cmap + 2, end, &tableSize))
             return 0;
 
-        quint16 firstCode6;
+        quint16 firstCode6 = 0;
         if (!qSafeFromBigEndian(cmap + 6, end, &firstCode6))
             return 0;
         if (unicode < firstCode6)
             return 0;
 
-        quint16 entryCount6;
+        quint16 entryCount6 = 0;
         if (!qSafeFromBigEndian(cmap + 8, end, &entryCount6))
             return 0;
         if (entryCount6 * 2 + 10 > tableSize)
@@ -1405,7 +1405,7 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
         qSafeFromBigEndian(cmap + 10 + (entryIndex6 * 2), end, &index);
         return index;
     } else if (format == 12) {
-        quint32 nGroups;
+        quint32 nGroups = 0;
         if (!qSafeFromBigEndian(cmap + 12, end, &nGroups))
             return 0;
 
@@ -1415,19 +1415,19 @@ quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint
         while (left <= right) {
             int middle = left + ( ( right - left ) >> 1 );
 
-            quint32 startCharCode;
+            quint32 startCharCode = 0;
             if (!qSafeFromBigEndian(cmap + 12 * middle, end, &startCharCode))
                 return 0;
 
             if (unicode < startCharCode)
                 right = middle - 1;
             else {
-                quint32 endCharCode;
+                quint32 endCharCode = 0;
                 if (!qSafeFromBigEndian(cmap + 12 * middle + 4, end, &endCharCode))
                     return 0;
 
                 if (unicode <= endCharCode) {
-                    quint32 index;
+                    quint32 index = 0;
                     if (!qSafeFromBigEndian(cmap + 12 * middle + 8, end, &index))
                         return 0;