From f5082ad3a7a4065eb95d6153ae1e0b5cdc938235 Mon Sep 17 00:00:00 2001
From: Jeff Genovy <29107334+jefgen@users.noreply.github.com>
Date: Wed, 2 May 2018 06:49:00 +0000
Subject: [PATCH] ICU-13725 Fix many of the C4251 warnings by DLL-exporting
 explicit template instantiations.

X-SVN-Rev: 41306
---
 icu4c/source/i18n/number_utils.h          | 11 ++++++++++-
 icu4c/source/i18n/numparse_affixes.h      | 13 +++++++++++++
 icu4c/source/i18n/numparse_compositions.h |  6 ++++++
 icu4c/source/i18n/numparse_impl.h         |  7 +++++++
 4 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/icu4c/source/i18n/number_utils.h b/icu4c/source/i18n/number_utils.h
index bd35e21c705..2fdbb68b40b 100644
--- a/icu4c/source/i18n/number_utils.h
+++ b/icu4c/source/i18n/number_utils.h
@@ -115,6 +115,15 @@ getPatternForStyle(const Locale& locale, const char* nsName, CldrPatternStyle st
 } // namespace utils
 
 
+#define DECNUM_INITIAL_CAPACITY 34
+
+  // Export an explicit template instantiation of the MaybeStackHeaderAndArray that is used as a data member of DecNum.
+  // When building DLLs for Windows this is required even though no direct access to the MaybeStackHeaderAndArray leaks out of the i18n library.
+  // (See digitlst.h, pluralaffix.h, datefmt.h, and others for similar examples.)
+#if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN
+template class U_I18N_API MaybeStackHeaderAndArray<decNumber, char, DECNUM_INITIAL_CAPACITY>;
+#endif
+
 /** A very thin C++ wrapper around decNumber.h */
 // Exported as U_I18N_API for tests
 class U_I18N_API DecNum : public UMemory {
@@ -151,7 +160,7 @@ class U_I18N_API DecNum : public UMemory {
     }
 
   private:
-    static constexpr int32_t kDefaultDigits = 34;
+    static constexpr int32_t kDefaultDigits = DECNUM_INITIAL_CAPACITY;
     MaybeStackHeaderAndArray<decNumber, char, kDefaultDigits> fData;
     decContext fContext;
 
diff --git a/icu4c/source/i18n/numparse_affixes.h b/icu4c/source/i18n/numparse_affixes.h
index 933dcc7ea45..5318cf6d41c 100644
--- a/icu4c/source/i18n/numparse_affixes.h
+++ b/icu4c/source/i18n/numparse_affixes.h
@@ -44,6 +44,13 @@ class CodePointMatcher : public NumberParseMatcher, public UMemory {
 };
 
 
+// Export an explicit template instantiation of the MaybeStackArray that is used as a data member of CodePointMatcherWarehouse.
+// When building DLLs for Windows this is required even though no direct access to the MaybeStackArray leaks out of the i18n library.
+// (See numparse_compositions.h, digitlst.h, pluralaffix.h, datefmt.h, and others for similar examples.)
+#if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN
+template class U_I18N_API MaybeStackArray<CodePointMatcher*, 3>;
+#endif
+
 /**
  * A warehouse to retain ownership of CodePointMatchers.
  */
@@ -155,6 +162,12 @@ class AffixPatternMatcherBuilder : public TokenConsumer, public MutableMatcherCo
     void addMatcher(NumberParseMatcher& matcher) override;
 };
 
+// Export an explicit template instantiation of the CompactUnicodeString that is used as a data member of AffixPatternMatcher.
+// When building DLLs for Windows this is required even though no direct access to the CompactUnicodeString leaks out of the i18n library.
+// (See digitlst.h, pluralaffix.h, datefmt.h, and others for similar examples.)
+#if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN
+template class U_I18N_API CompactUnicodeString<4>;
+#endif
 
 // Exported as U_I18N_API for tests
 class U_I18N_API AffixPatternMatcher : public ArraySeriesMatcher {
diff --git a/icu4c/source/i18n/numparse_compositions.h b/icu4c/source/i18n/numparse_compositions.h
index 80aeb66e647..2a993928da8 100644
--- a/icu4c/source/i18n/numparse_compositions.h
+++ b/icu4c/source/i18n/numparse_compositions.h
@@ -78,6 +78,12 @@ class U_I18N_API SeriesMatcher : public CompositionMatcher {
     SeriesMatcher() = default;
 };
 
+// Export an explicit template instantiation of the MaybeStackArray that is used as a data member of ArraySeriesMatcher.
+// When building DLLs for Windows this is required even though no direct access to the MaybeStackArray leaks out of the i18n library.
+// (See digitlst.h, pluralaffix.h, datefmt.h, and others for similar examples.)
+#if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN
+template class U_I18N_API MaybeStackArray<const NumberParseMatcher*, 3>;
+#endif
 
 /**
  * An implementation of SeriesMatcher that references an array of matchers.
diff --git a/icu4c/source/i18n/numparse_impl.h b/icu4c/source/i18n/numparse_impl.h
index e4eac0e9c09..63c04802441 100644
--- a/icu4c/source/i18n/numparse_impl.h
+++ b/icu4c/source/i18n/numparse_impl.h
@@ -22,6 +22,13 @@
 U_NAMESPACE_BEGIN namespace numparse {
 namespace impl {
 
+// Export an explicit template instantiation of the MaybeStackArray that is used as a data member of NumberParserImpl.
+// When building DLLs for Windows this is required even though no direct access to the MaybeStackArray leaks out of the i18n library.
+// (See numparse_compositions.h, numparse_affixes.h, datefmt.h, and others for similar examples.)
+#if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN
+template class U_I18N_API MaybeStackArray<const NumberParseMatcher*, 10>;
+#endif
+
 // Exported as U_I18N_API for tests
 class U_I18N_API NumberParserImpl : public MutableMatcherCollection {
   public: