Fix specific overflow in qtextlayout

Adds qAddOverflow and qMulOverflow definitions to QFixed

Fixes: QTBUG-113337
Pick-to: 6.5 6.5.1 6.2 5.15
Change-Id: I13579306defceaccdc0fbb1ec0e9b77c6f8d1af9
Reviewed-by: Eirik Aavitsland <[email protected]>
Reviewed-by: Thiago Macieira <[email protected]>

1 files changed, 6 insertions, 3 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index b8edea11d5f..611369951c7 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -2164,9 +2164,12 @@ found:
         eng->maxWidth = qMax(eng->maxWidth, line.textWidth);
     } else {
         eng->minWidth = qMax(eng->minWidth, lbh.minw);
-        eng->layoutData->currentMaxWidth += line.textWidth;
-        if (!manuallyWrapped)
-            eng->layoutData->currentMaxWidth += lbh.spaceData.textWidth;
+        if (qAddOverflow(eng->layoutData->currentMaxWidth, line.textWidth, &eng->layoutData->currentMaxWidth))
+            eng->layoutData->currentMaxWidth = QFIXED_MAX;
+        if (!manuallyWrapped) {
+            if (qAddOverflow(eng->layoutData->currentMaxWidth, lbh.spaceData.textWidth, &eng->layoutData->currentMaxWidth))
+                eng->layoutData->currentMaxWidth = QFIXED_MAX;
+        }
         eng->maxWidth = qMax(eng->maxWidth, eng->layoutData->currentMaxWidth);
         if (manuallyWrapped)
             eng->layoutData->currentMaxWidth = 0;