diff --git a/Help/policy/CMP0049.rst b/Help/policy/CMP0049.rst
index d12ef8832e..c2500cd60a 100644
--- a/Help/policy/CMP0049.rst
+++ b/Help/policy/CMP0049.rst
@@ -1,6 +1,9 @@
 CMP0049
 -------
 
+.. |REMOVED_IN_CMAKE_VERSION| replace:: 4.0
+.. include:: REMOVED_PROLOGUE.txt
+
 Do not expand variables in target source entries.
 
 CMake 2.8.12 and lower performed an extra layer of variable expansion
@@ -18,7 +21,5 @@ the target sources.  The ``NEW`` behavior for this policy is to issue an error
 if such variables need to be expanded.
 
 .. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.0
-.. |WARNS_OR_DOES_NOT_WARN| replace:: warns
-.. include:: STANDARD_ADVICE.txt
-
-.. include:: DEPRECATED.txt
+.. |WARNED_OR_DID_NOT_WARN| replace:: warned
+.. include:: REMOVED_EPILOGUE.txt
diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h
index 62c21f48c0..53d0683b4e 100644
--- a/Source/cmPolicies.h
+++ b/Source/cmPolicies.h
@@ -147,7 +147,7 @@ class cmMakefile;
   SELECT(POLICY, CMP0048, "project() command manages VERSION variables.", 3,  \
          0, 0, NEW)                                                           \
   SELECT(POLICY, CMP0049,                                                     \
-         "Do not expand variables in target source entries.", 3, 0, 0, WARN)  \
+         "Do not expand variables in target source entries.", 3, 0, 0, NEW)   \
   SELECT(POLICY, CMP0050, "Disallow add_custom_command SOURCE signatures.",   \
          3, 0, 0, WARN)                                                       \
   SELECT(POLICY, CMP0051, "List TARGET_OBJECTS in SOURCES target property.",  \
diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index a95665f0f8..c75462820f 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -682,8 +682,6 @@ public:
   bool CheckImportedLibName(std::string const& prop,
                             std::string const& value) const;
 
-  std::string ProcessSourceItemCMP0049(const std::string& s) const;
-
   template <typename ValueType>
   void AddDirectoryToFileSet(cmTarget* self, std::string const& fileSetName,
                              ValueType value, cm::string_view fileSetType,
@@ -1368,14 +1366,8 @@ void cmTarget::AddTracedSources(std::vector<std::string> const& srcs)
 void cmTarget::AddSources(std::vector<std::string> const& srcs)
 {
   std::vector<std::string> srcFiles;
-  for (auto filename : srcs) {
+  for (std::string const& filename : srcs) {
     if (!cmGeneratorExpression::StartsWithGeneratorExpression(filename)) {
-      if (!filename.empty()) {
-        filename = this->impl->ProcessSourceItemCMP0049(filename);
-        if (filename.empty()) {
-          return;
-        }
-      }
       this->impl->Makefile->GetOrCreateSource(filename);
     }
     srcFiles.emplace_back(filename);
@@ -1383,47 +1375,6 @@ void cmTarget::AddSources(std::vector<std::string> const& srcs)
   this->AddTracedSources(srcFiles);
 }
 
-std::string cmTargetInternals::ProcessSourceItemCMP0049(
-  const std::string& s) const
-{
-  std::string src = s;
-
-  // For backwards compatibility replace variables in source names.
-  // This should eventually be removed.
-  this->Makefile->ExpandVariablesInString(src);
-  if (src != s) {
-    std::ostringstream e;
-    bool noMessage = false;
-    MessageType messageType = MessageType::AUTHOR_WARNING;
-    switch (this->Makefile->GetPolicyStatus(cmPolicies::CMP0049)) {
-      case cmPolicies::WARN:
-        e << cmPolicies::GetPolicyWarning(cmPolicies::CMP0049) << "\n";
-        break;
-      case cmPolicies::OLD:
-        noMessage = true;
-        break;
-      case cmPolicies::NEW:
-        messageType = MessageType::FATAL_ERROR;
-    }
-    if (!noMessage) {
-      e << "Legacy variable expansion in source file \"" << s
-        << "\" expanded to \"" << src << "\" in target \"" << this->Name
-        << "\".  This behavior will be removed in a "
-           "future version of CMake.";
-      this->Makefile->IssueMessage(messageType, e.str());
-      if (messageType == MessageType::FATAL_ERROR) {
-        return "";
-      }
-    }
-  }
-  return src;
-}
-
-std::string cmTarget::GetSourceCMP0049(const std::string& s)
-{
-  return this->impl->ProcessSourceItemCMP0049(s);
-}
-
 struct CreateLocation
 {
   cmMakefile const* Makefile;
diff --git a/Source/cmTarget.h b/Source/cmTarget.h
index 3a515d5b50..246e184515 100644
--- a/Source/cmTarget.h
+++ b/Source/cmTarget.h
@@ -113,7 +113,6 @@ public:
   //! Add sources to the target.
   void AddSources(std::vector<std::string> const& srcs);
   void AddTracedSources(std::vector<std::string> const& srcs);
-  std::string GetSourceCMP0049(const std::string& src);
   cmSourceFile* AddSource(const std::string& src, bool before = false);
 
   //! how we identify a library, by name and type
diff --git a/Tests/RunCMake/CMP0049/CMP0049-NEW-stderr.txt b/Tests/RunCMake/CMP0049/CMP0049-NEW-stderr.txt
index ff787e8476..b22cc4e96b 100644
--- a/Tests/RunCMake/CMP0049/CMP0049-NEW-stderr.txt
+++ b/Tests/RunCMake/CMP0049/CMP0049-NEW-stderr.txt
@@ -1,6 +1,9 @@
-CMake Error at CMP0049-NEW.cmake:5 \(add_library\):
-  Legacy variable expansion in source file "\${tgt_srcs}" expanded to
-  "empty.cpp" in target "tgt".  This behavior will be removed in a future
-  version of CMake.
-Call Stack \(most recent call first\):
+CMake Error at CMP0049-NEW.cmake:[0-9]+ \(add_library\):
+  Cannot find source file:
+
+    \${tgt_srcs}
+
+  Tried extensions ([^
+]+
+)+Call Stack \(most recent call first\):
   CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/CMP0049/CMP0049-NEW.cmake b/Tests/RunCMake/CMP0049/CMP0049-NEW.cmake
index 85b5aa8546..ce4cded68b 100644
--- a/Tests/RunCMake/CMP0049/CMP0049-NEW.cmake
+++ b/Tests/RunCMake/CMP0049/CMP0049-NEW.cmake
@@ -1,5 +1,2 @@
-
-cmake_policy(SET CMP0049 NEW)
-
 set(tgt_srcs empty.cpp)
 add_library(tgt \${tgt_srcs})
diff --git a/Tests/RunCMake/CMP0049/CMP0049-OLD-stderr.txt b/Tests/RunCMake/CMP0049/CMP0049-OLD-stderr.txt
deleted file mode 100644
index b3739705bd..0000000000
--- a/Tests/RunCMake/CMP0049/CMP0049-OLD-stderr.txt
+++ /dev/null
@@ -1,10 +0,0 @@
-^CMake Deprecation Warning at CMP0049-OLD.cmake:2 \(cmake_policy\):
-  The OLD behavior for policy CMP0049 will be removed from a future version
-  of CMake.
-
-  The cmake-policies\(7\) manual explains that the OLD behaviors of all
-  policies are deprecated and that a policy should be set to OLD only under
-  specific short-term circumstances.  Projects should be ported to the NEW
-  behavior and not rely on setting a policy to OLD.
-Call Stack \(most recent call first\):
-  CMakeLists.txt:3 \(include\)$
diff --git a/Tests/RunCMake/CMP0049/CMP0049-OLD.cmake b/Tests/RunCMake/CMP0049/CMP0049-OLD.cmake
deleted file mode 100644
index ae6fd3bcdf..0000000000
--- a/Tests/RunCMake/CMP0049/CMP0049-OLD.cmake
+++ /dev/null
@@ -1,5 +0,0 @@
-
-cmake_policy(SET CMP0049 OLD)
-
-set(tgt_srcs empty.cpp)
-add_library(tgt \${tgt_srcs})
diff --git a/Tests/RunCMake/CMP0049/CMP0049-WARN-result.txt b/Tests/RunCMake/CMP0049/CMP0049-WARN-result.txt
deleted file mode 100644
index 573541ac97..0000000000
--- a/Tests/RunCMake/CMP0049/CMP0049-WARN-result.txt
+++ /dev/null
@@ -1 +0,0 @@
-0
diff --git a/Tests/RunCMake/CMP0049/CMP0049-WARN-stderr.txt b/Tests/RunCMake/CMP0049/CMP0049-WARN-stderr.txt
deleted file mode 100644
index 0cf5ce354a..0000000000
--- a/Tests/RunCMake/CMP0049/CMP0049-WARN-stderr.txt
+++ /dev/null
@@ -1,11 +0,0 @@
-CMake Warning \(dev\) at CMP0049-WARN.cmake:3 \(add_library\):
-  Policy CMP0049 is not set: Do not expand variables in target source
-  entries.  Run "cmake --help-policy CMP0049" for policy details.  Use the
-  cmake_policy command to set the policy and suppress this warning.
-
-  Legacy variable expansion in source file "\${tgt_srcs}" expanded to
-  "empty.cpp" in target "tgt".  This behavior will be removed in a future
-  version of CMake.
-Call Stack \(most recent call first\):
-  CMakeLists.txt:3 \(include\)
-This warning is for project developers.  Use -Wno-dev to suppress it.
diff --git a/Tests/RunCMake/CMP0049/CMP0049-WARN.cmake b/Tests/RunCMake/CMP0049/CMP0049-WARN.cmake
deleted file mode 100644
index ada082e610..0000000000
--- a/Tests/RunCMake/CMP0049/CMP0049-WARN.cmake
+++ /dev/null
@@ -1,3 +0,0 @@
-
-set(tgt_srcs empty.cpp)
-add_library(tgt \${tgt_srcs})
diff --git a/Tests/RunCMake/CMP0049/CMakeLists.txt b/Tests/RunCMake/CMP0049/CMakeLists.txt
index a06591c31f..c814f14935 100644
--- a/Tests/RunCMake/CMP0049/CMakeLists.txt
+++ b/Tests/RunCMake/CMP0049/CMakeLists.txt
@@ -1,3 +1,3 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 3.10)
 project(${RunCMake_TEST} CXX)
 include(${RunCMake_TEST}.cmake)
diff --git a/Tests/RunCMake/CMP0049/RunCMakeTest.cmake b/Tests/RunCMake/CMP0049/RunCMakeTest.cmake
index e71f31e87b..70b2b44dd5 100644
--- a/Tests/RunCMake/CMP0049/RunCMakeTest.cmake
+++ b/Tests/RunCMake/CMP0049/RunCMakeTest.cmake
@@ -1,6 +1,3 @@
 include(RunCMake)
-set(RunCMake_IGNORE_POLICY_VERSION_DEPRECATION ON)
 
-run_cmake(CMP0049-OLD)
 run_cmake(CMP0049-NEW)
-run_cmake(CMP0049-WARN)