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, 2 insertions, 2 deletions

diff --git a/src/widgets/widgets/qlcdnumber.cpp b/src/widgets/widgets/qlcdnumber.cpp
index 2703e5d8a3..aa052ef5cb 100644
--- a/src/widgets/widgets/qlcdnumber.cpp
+++ b/src/widgets/widgets/qlcdnumber.cpp
@@ -188,8 +188,8 @@ static QString int2string(int num, int base, int ndigits, bool *oflow)
                 } while (n != 0);
                 len = ndigits - len;
                 if (len > 0)
-                s.fill(QLatin1Char(' '), len);
-                s += QString::fromLatin1(p);
+                    s += QString(len, QLatin1Char(' '));
+                s += QLatin1String(p);
             }
             break;
     }