From 47b9a517be000559499dcfcb2ed62eace740e194 Mon Sep 17 00:00:00 2001
From: Mihai Nita <nmihai_2000@yahoo.com>
Date: Wed, 17 Jan 2024 05:31:38 +0000
Subject: [PATCH] ICU-21107 Specify language standard versions C11 & C++17 also
 for MSVC

ICU-21107 Specify language standard versions C11 & C++17 also for MSVC
---
 .../Build.Windows.ProjectConfiguration.props  |   3 +
 ...ild.Windows.UWP.ProjectConfiguration.props |   3 +
 icu4c/source/common/common.vcxproj            |   3 -
 icu4c/source/common/common_uwp.vcxproj        |   3 -
 icu4c/source/extra/uconv/uconv.vcxproj        |   3 -
 icu4c/source/i18n/calendar.cpp                |  12 +-
 icu4c/source/i18n/i18n.vcxproj                |   3 -
 icu4c/source/i18n/i18n_uwp.vcxproj            |   3 -
 icu4c/source/io/io.vcxproj                    |   3 -
 icu4c/source/layoutex/layoutex.vcxproj        |  18 +--
 icu4c/source/samples/break/break.vcxproj      |   2 -
 icu4c/source/samples/cal/cal.vcxproj          |   3 -
 icu4c/source/samples/case/case.vcxproj        |   3 -
 icu4c/source/samples/citer/citer.vcxproj      |   6 -
 icu4c/source/samples/coll/coll.vcxproj        |   6 -
 icu4c/source/samples/csdet/csdet.vcxproj      |   6 -
 icu4c/source/samples/date/date.vcxproj        |   6 -
 icu4c/source/samples/datefmt/datefmt.vcxproj  |   6 -
 .../dtitvfmtsample/dtitvfmtsample.vcxproj     |   6 -
 .../samples/dtptngsample/dtptngsample.vcxproj |   6 -
 icu4c/source/samples/layout/layout.vcxproj    |   6 -
 icu4c/source/samples/legacy/legacy.vcxproj    |   8 +-
 icu4c/source/samples/msgfmt/msgfmt.vcxproj    |   6 -
 icu4c/source/samples/numfmt/numfmt.vcxproj    |   6 -
 .../plurfmtsample/plurfmtsample.vcxproj       |   6 -
 icu4c/source/samples/props/props.vcxproj      |   6 -
 icu4c/source/samples/strsrch/strsrch.vcxproj  |   6 -
 .../source/samples/translit/translit.vcxproj  |   2 -
 icu4c/source/samples/uciter8/uciter8.vcxproj  |   2 -
 icu4c/source/samples/ucnv/ucnv.vcxproj        |   2 -
 icu4c/source/samples/udata/reader.vcxproj     |   6 -
 icu4c/source/samples/udata/writer.vcxproj     |   6 -
 .../source/samples/ufortune/ufortune.vcxproj  |   2 -
 icu4c/source/samples/ugrep/ugrep.vcxproj      |   6 -
 icu4c/source/samples/uresb/uresb.vcxproj      |   2 -
 icu4c/source/samples/ustring/ustring.vcxproj  |   2 -
 icu4c/source/stubdata/stubdata.vcxproj        |   3 -
 icu4c/source/test/cintltst/cintltst.vcxproj   |   3 -
 icu4c/source/test/intltest/intltest.vcxproj   | 107 +++++-------------
 icu4c/source/test/iotest/iotest.vcxproj       |   4 -
 icu4c/source/test/letest/cletest.vcxproj      |   8 +-
 icu4c/source/test/letest/gendata.vcxproj      |   8 +-
 icu4c/source/test/letest/letest.vcxproj       |   8 +-
 .../test/perf/DateFmtPerf/DateFmtPerf.vcxproj |   6 -
 .../test/perf/charperf/charperf.vcxproj       |   6 -
 .../test/perf/collperf/collperf.vcxproj       |   6 -
 .../test/perf/collperf2/collperf2.vcxproj     |   8 +-
 .../test/perf/convperf/convperf.vcxproj       |   6 -
 .../test/perf/normperf/dtfmtrtperf.vcxproj    |   8 +-
 .../test/perf/normperf/normperf.vcxproj       |   6 -
 .../test/perf/strsrchperf/strsrchperf.vcxproj |   6 -
 .../test/perf/ubrkperf/ubrkperf.vcxproj       |   6 -
 .../perf/ucnvavailperf/ucnvavailperf.vcxproj  |   6 -
 .../test/perf/unisetperf/unisetperf.vcxproj   |   6 -
 .../test/perf/usetperf/usetperf.vcxproj       |   6 -
 .../test/perf/ustrperf/stringperf.vcxproj     |   6 -
 .../source/test/perf/utfperf/utfperf.vcxproj  |   6 -
 .../test/perf/utrie2perf/utrie2perf.vcxproj   |   6 -
 icu4c/source/tools/ctestfw/ctestfw.vcxproj    |  19 +---
 icu4c/source/tools/genbrk/genbrk.vcxproj      |   3 -
 icu4c/source/tools/genccode/genccode.vcxproj  |   3 -
 icu4c/source/tools/gencfu/gencfu.vcxproj      |   3 -
 icu4c/source/tools/gencmn/gencmn.vcxproj      |   3 -
 icu4c/source/tools/gencnval/gencnval.vcxproj  |   3 -
 icu4c/source/tools/gendict/gendict.vcxproj    |   3 -
 icu4c/source/tools/gennorm2/gennorm2.vcxproj  |   3 -
 icu4c/source/tools/genrb/derb.vcxproj         |   3 -
 icu4c/source/tools/genrb/genrb.vcxproj        |  23 +---
 icu4c/source/tools/gensprep/gensprep.vcxproj  |   3 -
 icu4c/source/tools/gentest/gentest.vcxproj    |   3 -
 .../tools/icuexportdata/icuexportdata.vcxproj |   3 -
 icu4c/source/tools/icuinfo/icuinfo.vcxproj    |   3 -
 icu4c/source/tools/icuinfo/testplug.vcxproj   |   3 -
 icu4c/source/tools/icupkg/icupkg.vcxproj      |   3 -
 icu4c/source/tools/icuswap/icuswap.vcxproj    |  12 +-
 icu4c/source/tools/makeconv/makeconv.vcxproj  |   3 -
 icu4c/source/tools/pkgdata/pkgdata.vcxproj    |   3 -
 icu4c/source/tools/toolutil/toolutil.vcxproj  |  43 ++-----
 icu4c/source/tools/tzcode/icuzdump.vcxproj    |   9 +-
 79 files changed, 76 insertions(+), 491 deletions(-)

diff --git a/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props b/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props
index 5d7e3344889..222c0aa0b80 100644
--- a/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props
+++ b/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props
@@ -96,6 +96,9 @@
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
       <!-- Enable parallel compilation for faster builds. -->
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
+      <!-- Set the C/C++ versions supported. -->
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
     </ClCompile>
     <ResourceCompile>
       <Culture>0x0409</Culture>
diff --git a/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props b/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props
index 948b7c4f98b..12c29b3291b 100644
--- a/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props
+++ b/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props
@@ -45,6 +45,9 @@
         %(PreprocessorDefinitions);
         U_PLATFORM_HAS_WINUWP_API=1;
       </PreprocessorDefinitions>
+      <!-- Set the C/C++ versions supported. -->
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
     </ClCompile>
     <ResourceCompile>
       <PreprocessorDefinitions>
diff --git a/icu4c/source/common/common.vcxproj b/icu4c/source/common/common.vcxproj
index 56fe146ed7a..1fdf3bda895 100644
--- a/icu4c/source/common/common.vcxproj
+++ b/icu4c/source/common/common.vcxproj
@@ -34,10 +34,7 @@
       <TypeLibraryName>$(OutDir)\icuuc.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <PreprocessorDefinitions>U_ATTRIBUTE_DEPRECATED=;U_COMMON_IMPLEMENTATION;U_PLATFORM_USES_ONLY_WIN32_API=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
diff --git a/icu4c/source/common/common_uwp.vcxproj b/icu4c/source/common/common_uwp.vcxproj
index 7379eade57f..177455dc57b 100644
--- a/icu4c/source/common/common_uwp.vcxproj
+++ b/icu4c/source/common/common_uwp.vcxproj
@@ -72,8 +72,6 @@
       <TypeLibraryName>$(OutDir)\icuuc.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <!-- U_DISABLE_RENAMING -->
       <!-- U_HIDE_DRAFT_API & U_HIDE_DEPRECATED_API -->
@@ -82,7 +80,6 @@
       <ExceptionHandling>
       </ExceptionHandling>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <TreatWChar_tAsBuiltInType>true</TreatWChar_tAsBuiltInType>
       <WarningLevel>Level3</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
diff --git a/icu4c/source/extra/uconv/uconv.vcxproj b/icu4c/source/extra/uconv/uconv.vcxproj
index adfe06c87d3..a0cc5adf092 100644
--- a/icu4c/source/extra/uconv/uconv.vcxproj
+++ b/icu4c/source/extra/uconv/uconv.vcxproj
@@ -34,11 +34,8 @@
       <TypeLibraryName>$(OutDir)\uconv.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <AdditionalIncludeDirectories>..\..\..\include;..\..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>UCONVMSG_LINK;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PrecompiledHeaderOutputFile>$(OutDir)\uconv.pch</PrecompiledHeaderOutputFile>
diff --git a/icu4c/source/i18n/calendar.cpp b/icu4c/source/i18n/calendar.cpp
index 2bd2cc9aa9d..33050553488 100644
--- a/icu4c/source/i18n/calendar.cpp
+++ b/icu4c/source/i18n/calendar.cpp
@@ -3695,13 +3695,15 @@ int32_t Calendar::handleGetExtendedYearFromWeekFields(int32_t yearWoy, int32_t w
 
 int32_t Calendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const
 {
-    return handleComputeMonthStart(extendedYear, month+1, true) -
-        handleComputeMonthStart(extendedYear, month, true);
+    const int32_t nextMonthStart = handleComputeMonthStart(extendedYear, month+1, true);
+    const int32_t thisMonthStart = handleComputeMonthStart(extendedYear, month, true);
+    return nextMonthStart - thisMonthStart;
 }
 
-int32_t Calendar::handleGetYearLength(int32_t eyear) const {
-    int32_t nextYearStart = handleComputeMonthStart(eyear + 1, 0, false);
-    int32_t thisYearStart = handleComputeMonthStart(eyear, 0, false);
+int32_t Calendar::handleGetYearLength(int32_t eyear) const
+{
+    const int32_t nextYearStart = handleComputeMonthStart(eyear + 1, 0, false);
+    const int32_t thisYearStart = handleComputeMonthStart(eyear, 0, false);
     return nextYearStart - thisYearStart;
 }
 
diff --git a/icu4c/source/i18n/i18n.vcxproj b/icu4c/source/i18n/i18n.vcxproj
index a9622aa45e9..55471bef149 100644
--- a/icu4c/source/i18n/i18n.vcxproj
+++ b/icu4c/source/i18n/i18n.vcxproj
@@ -34,10 +34,7 @@
       <TypeLibraryName>$(OutDir)\icuin.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <PreprocessorDefinitions>U_ATTRIBUTE_DEPRECATED=;U_I18N_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <WarningLevel>Level3</WarningLevel>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <CompileAs>Default</CompileAs>
diff --git a/icu4c/source/i18n/i18n_uwp.vcxproj b/icu4c/source/i18n/i18n_uwp.vcxproj
index f389562d058..dd997d11580 100644
--- a/icu4c/source/i18n/i18n_uwp.vcxproj
+++ b/icu4c/source/i18n/i18n_uwp.vcxproj
@@ -70,8 +70,6 @@
       <SuppressStartupBanner>true</SuppressStartupBanner>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <!-- U_DISABLE_RENAMING -->
       <!-- U_HIDE_DRAFT_API & U_HIDE_DEPRECATED_API -->
@@ -80,7 +78,6 @@
       <ExceptionHandling>
       </ExceptionHandling>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <TreatWChar_tAsBuiltInType>true</TreatWChar_tAsBuiltInType>
       <WarningLevel>Level3</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
diff --git a/icu4c/source/io/io.vcxproj b/icu4c/source/io/io.vcxproj
index bad5d666ebd..b4b31a6d090 100644
--- a/icu4c/source/io/io.vcxproj
+++ b/icu4c/source/io/io.vcxproj
@@ -34,11 +34,8 @@
       <TypeLibraryName>$(OutDir)\icuio.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>U_IO_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
diff --git a/icu4c/source/layoutex/layoutex.vcxproj b/icu4c/source/layoutex/layoutex.vcxproj
index 0445eeed748..41fdacec7d7 100644
--- a/icu4c/source/layoutex/layoutex.vcxproj
+++ b/icu4c/source/layoutex/layoutex.vcxproj
@@ -34,8 +34,6 @@
     <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>U_LAYOUTEX_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <WarningLevel>Level3</WarningLevel>
@@ -48,7 +46,6 @@
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x86\Release/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x86\Release/</AssemblerListingLocation>
       <ObjectFileName>.\x86\Release/</ObjectFileName>
@@ -71,7 +68,6 @@
     </Midl>
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x86\Debug/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x86\Debug/</AssemblerListingLocation>
       <ObjectFileName>.\x86\Debug/</ObjectFileName>
@@ -98,7 +94,6 @@
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x64\Release/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x64\Release/</AssemblerListingLocation>
       <ObjectFileName>.\x64\Release/</ObjectFileName>
@@ -119,7 +114,6 @@
     </Midl>
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x64\Debug/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x64\Debug/</AssemblerListingLocation>
       <ObjectFileName>.\x64\Debug/</ObjectFileName>
@@ -140,15 +134,9 @@
   <ItemGroup>
     <ClCompile Include="LXUtilities.cpp" />
     <ClCompile Include="ParagraphLayout.cpp" />
-    <ClCompile Include="playout.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
-    <ClCompile Include="plruns.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
-    <ClCompile Include="RunArrays.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
+    <ClCompile Include="playout.cpp" />
+    <ClCompile Include="plruns.cpp" />
+    <ClCompile Include="RunArrays.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="LXUtilities.h" />
diff --git a/icu4c/source/samples/break/break.vcxproj b/icu4c/source/samples/break/break.vcxproj
index 59a93b56ed3..d9a51001d2a 100644
--- a/icu4c/source/samples/break/break.vcxproj
+++ b/icu4c/source/samples/break/break.vcxproj
@@ -33,8 +33,6 @@
   <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
     </ClCompile>
diff --git a/icu4c/source/samples/cal/cal.vcxproj b/icu4c/source/samples/cal/cal.vcxproj
index aee2c34333c..2051033546d 100644
--- a/icu4c/source/samples/cal/cal.vcxproj
+++ b/icu4c/source/samples/cal/cal.vcxproj
@@ -33,11 +33,8 @@
   <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
diff --git a/icu4c/source/samples/case/case.vcxproj b/icu4c/source/samples/case/case.vcxproj
index f0c4122e48c..ab24c9344b3 100644
--- a/icu4c/source/samples/case/case.vcxproj
+++ b/icu4c/source/samples/case/case.vcxproj
@@ -33,11 +33,8 @@
   <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
diff --git a/icu4c/source/samples/citer/citer.vcxproj b/icu4c/source/samples/citer/citer.vcxproj
index 68e4fadeb2f..c9211442449 100644
--- a/icu4c/source/samples/citer/citer.vcxproj
+++ b/icu4c/source/samples/citer/citer.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\x64\Release\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Release|x64'">false</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
diff --git a/icu4c/source/samples/coll/coll.vcxproj b/icu4c/source/samples/coll/coll.vcxproj
index f58b0521715..fd49d1b8915 100644
--- a/icu4c/source/samples/coll/coll.vcxproj
+++ b/icu4c/source/samples/coll/coll.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">.\x64\Debug\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Midl>
       <TypeLibraryName>.\x86\Release/coll.tlb</TypeLibraryName>
diff --git a/icu4c/source/samples/csdet/csdet.vcxproj b/icu4c/source/samples/csdet/csdet.vcxproj
index 74d4ad57dd1..234a7b84e68 100644
--- a/icu4c/source/samples/csdet/csdet.vcxproj
+++ b/icu4c/source/samples/csdet/csdet.vcxproj
@@ -31,12 +31,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\x64\Release\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Release|x64'">false</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <AdditionalIncludeDirectories>../../../include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
diff --git a/icu4c/source/samples/date/date.vcxproj b/icu4c/source/samples/date/date.vcxproj
index e5d34f37345..3d20f9576ed 100644
--- a/icu4c/source/samples/date/date.vcxproj
+++ b/icu4c/source/samples/date/date.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">.\x64\Debug\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Midl>
       <TypeLibraryName>.\x86\Release/date.tlb</TypeLibraryName>
diff --git a/icu4c/source/samples/datefmt/datefmt.vcxproj b/icu4c/source/samples/datefmt/datefmt.vcxproj
index b1cf597f7b9..00dcd6d6700 100644
--- a/icu4c/source/samples/datefmt/datefmt.vcxproj
+++ b/icu4c/source/samples/datefmt/datefmt.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\x64\Release\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Release|x64'">false</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Midl>
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index 87bb4d9d632..c59d82de8d4 100644
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index d4f665be08f..079c4e879b5 100644
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