commit 4f72eea0261888239ce7822ba19af222eed22a48
author Robin Leroy <egg.robin.leroy@gmail.com> Tue Sep 24 17:38:26 2019 +0200
committer pedberg-icu <42151464+pedberg-icu@users.noreply.github.com> Wed Sep 25 16:30:15 2019 -0700
tree 9c27436a44f0846ed705885b650985a01d239116
parent 1f4a77cbc15981810a18e3af4b1a9acf6f508d09

ICU-20831 Make *fCapitalizationBrkIter const, eliminating a data race in SimpleDateFormat::format.

icu4c/source/i18n/smpdtfmt.cpp

diff --git a/icu4c/source/i18n/smpdtfmt.cpp b/icu4c/source/i18n/smpdtfmt.cpp
index b8edff4..5fcbb58 100644
--- a/icu4c/source/i18n/smpdtfmt.cpp
+++ b/icu4c/source/i18n/smpdtfmt.cpp
@@ -1981,9 +1981,11 @@
                 break;
         }
         if (titlecase) {
+            BreakIterator* const mutableCapitalizationBrkIter = fCapitalizationBrkIter->clone();
             UnicodeString firstField(appendTo, beginOffset);
-            firstField.toTitle(fCapitalizationBrkIter, fLocale, U_TITLECASE_NO_LOWERCASE | U_TITLECASE_NO_BREAK_ADJUSTMENT);
+            firstField.toTitle(mutableCapitalizationBrkIter, fLocale, U_TITLECASE_NO_LOWERCASE | U_TITLECASE_NO_BREAK_ADJUSTMENT);
             appendTo.replaceBetween(beginOffset, appendTo.length(), firstField);
+            delete mutableCapitalizationBrkIter;
         }
     }
 #endif

icu4c/source/i18n/unicode/smpdtfmt.h

diff --git a/icu4c/source/i18n/unicode/smpdtfmt.h b/icu4c/source/i18n/unicode/smpdtfmt.h
index 8a7a176..79fa817 100644
--- a/icu4c/source/i18n/unicode/smpdtfmt.h
+++ b/icu4c/source/i18n/unicode/smpdtfmt.h
@@ -1645,7 +1645,7 @@
 
     UBool fHaveDefaultCentury;
 
-    BreakIterator* fCapitalizationBrkIter;
+    const BreakIterator* fCapitalizationBrkIter;
 };
 
 inline UDate