commit 168c97f32ab669a5787898d2b01399a15edf6176
author Fredrik Roubert <roubert@google.com> Fri Feb 15 20:42:18 2019 +0100
committer Fredrik Roubert <fredrik@roubert.name> Wed Feb 20 13:06:51 2019 +0100
tree b691e9cf487e669e9f4db4f76b1990986b77747f
parent 8858da9b7ff006540b571fbc4c45f375447d1ae4

ICU-20431 Both und_XX and _XX should fall back to the default locale

icu4c/source/common/uresbund.cpp

diff --git a/icu4c/source/common/uresbund.cpp b/icu4c/source/common/uresbund.cpp
index 87c813c..050746d 100644
--- a/icu4c/source/common/uresbund.cpp
+++ b/icu4c/source/common/uresbund.cpp
@@ -489,6 +489,9 @@
 
         /*Fallback data stuff*/
         *hasChopped = chopLocale(name);
+        if (*hasChopped && *name == '\0') {
+            uprv_strcpy(name, "und");
+        }
     }
     return r;
 }

icu4c/source/test/intltest/dtptngts.cpp

diff --git a/icu4c/source/test/intltest/dtptngts.cpp b/icu4c/source/test/intltest/dtptngts.cpp
index 90c85e7..74c444f 100644
--- a/icu4c/source/test/intltest/dtptngts.cpp
+++ b/icu4c/source/test/intltest/dtptngts.cpp
@@ -1120,7 +1120,8 @@
     UErrorCode status = U_ZERO_ERROR;
     int32_t numTests = UPRV_LENGTHOF(tests);
     for (int32_t i = 0; i < numTests; ++i) {
-        DateTimePatternGenerator *gen = DateTimePatternGenerator::createInstance(Locale(tests[i][0]), status);
+        DateTimePatternGenerator *gen = DateTimePatternGenerator::createInstance(
+                Locale::forLanguageTag(tests[i][0], status), status);
         if (gen == NULL) {
             dataerrln("FAIL: DateTimePatternGenerator::createInstance failed for %s", tests[i][0]);
             return;