diff --git a/src/corelib/text/qlocale.cpp b/src/corelib/text/qlocale.cpp
index f318ec8316a..0d46506c764 100644
--- a/src/corelib/text/qlocale.cpp
+++ b/src/corelib/text/qlocale.cpp
@@ -4933,9 +4933,9 @@ QString QLocale::formattedDataSize(qint64 bytes, int precision, DataSizeFormats
     if (!bytes) {
         power = 0;
     } else if (format & DataSizeBase1000) {
-        power = int(std::log10(qAbs(bytes)) / 3);
+        power = int(std::log10(QtPrivate::qUnsignedAbs(bytes)) / 3);
     } else { // Compute log2(bytes) / 10:
-        power = int((63 - qCountLeadingZeroBits(quint64(qAbs(bytes)))) / 10);
+        power = int((63 - qCountLeadingZeroBits(QtPrivate::qUnsignedAbs(bytes))) / 10);
         base = 1024;
     }
     // Only go to doubles if we'll be using a quantifier:
diff --git a/tests/auto/corelib/text/qlocale/tst_qlocale.cpp b/tests/auto/corelib/text/qlocale/tst_qlocale.cpp
index 4c0dfe322f3..b8cacda937f 100644
--- a/tests/auto/corelib/text/qlocale/tst_qlocale.cpp
+++ b/tests/auto/corelib/text/qlocale/tst_qlocale.cpp
@@ -3970,9 +3970,7 @@ void tst_QLocale::formattedDataSize_data()
             ROWQ("IEC-1235k", 2, 1234567, "1", "18 Mi");
             ROWQ("IEC-1374k", 2, 1374744, "1", "31 Mi");
             ROWQ("IEC-1234M", 2, 1234567890, "1", "15 Gi");
-            if (false) { // hits UB
             ROWQ("IEC-min", 2, min64, "-8", "00 Ei");
-            }
             ROWQ("IEC-max", 2, max64, "8", "00 Ei");
         }
         {
@@ -3986,9 +3984,7 @@ void tst_QLocale::formattedDataSize_data()
             ROWQ("Trad--1235k", 2, -1234567, "-1", "18 M");
             ROWQ("Trad-1374k", 2, 1374744, "1", "31 M");
             ROWQ("Trad-1234M", 2, 1234567890, "1", "15 G");
-            if (false) { // hits UB
             ROWQ("Trad-min", 2, min64, "-8", "00 E");
-            }
             ROWQ("Trad-max", 2, max64, "8", "00 E");
         }
         {
@@ -4001,9 +3997,7 @@ void tst_QLocale::formattedDataSize_data()
             ROWQ("Decimal-1374k", 2, 1374744, "1", "37 M");
             ROWQ("Decimal-1234M", 2, 1234567890, "1", "23 G");
             ROWQ("Decimal--1234M", 2, -1234567890, "-1", "23 G");
-            if (false) { // hits UB
             ROWQ("Decimal-min", 2, min64, "-9", "22 E");
-            }
             ROWQ("Decimal-max", 2, max64, "9", "22 E");
         }
 #undef ROWQ