Use QString::fromLatin1() less to avoid string allocations

QString::fromLatin1 always allocates memory, but there are
cases where we can avoid/reduce allocations or/and reduce
text size, e.g.:

QStringBuilder expressions
Fix: replace QString::fromLatin1 with QL1S

QString::fromLatin1().arg(String) pattern
Fix: replace with QStringBuilder

Overloaded functions with QL1S arg
Fix: replace QString::fromLatin1 with QL1S

In rare cases if there is no overloaded function
with QL1S and we have deal with string literal,
replace QString::fromLatin1 with QStringLiteral.

Change-Id: Iabe1a3cc0830f40ef78a0548afa4368583c31def
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/gui/image/qimagereader.cpp b/src/gui/image/qimagereader.cpp
index 0320d032b0..4390e46fde 100644
--- a/src/gui/image/qimagereader.cpp
+++ b/src/gui/image/qimagereader.cpp
@@ -569,7 +569,7 @@ bool QImageReaderPrivate::initHandler()
 
         do {
             file->setFileName(fileName + QLatin1Char('.')
-                    + QString::fromLatin1(extensions.at(currentExtension++).constData()));
+                    + QLatin1String(extensions.at(currentExtension++).constData()));
             file->open(QIODevice::ReadOnly);
         } while (!file->isOpen() && currentExtension < extensions.size());