Index: llvm/docs/ReleaseNotes.rst
===================================================================
--- llvm/docs/ReleaseNotes.rst
+++ llvm/docs/ReleaseNotes.rst
@@ -184,6 +184,7 @@
   introduction of alternatives to zlib compression in the llvm toolchain.
   Changes are as follows:
   * Relocate the ``llvm::zlib`` namespace to ``llvm::compression::zlib``.
+  * Remove crc32 from zlib compression namespace, people should use the ``llvm::crc32`` instead.
 
 Changes to the Go bindings
 --------------------------
Index: llvm/include/llvm/Support/Compression.h
===================================================================
--- llvm/include/llvm/Support/Compression.h
+++ llvm/include/llvm/Support/Compression.h
@@ -42,8 +42,6 @@
                  SmallVectorImpl<char> &UncompressedBuffer,
                  size_t UncompressedSize);
 
-uint32_t crc32(StringRef Buffer);
-
 } // End of namespace zlib
 
 } // End of namespace compression
Index: llvm/lib/Support/Compression.cpp
===================================================================
--- llvm/lib/Support/Compression.cpp
+++ llvm/lib/Support/Compression.cpp
@@ -84,10 +84,6 @@
   return E;
 }
 
-uint32_t zlib::crc32(StringRef Buffer) {
-  return ::crc32(0, (const Bytef *)Buffer.data(), Buffer.size());
-}
-
 #else
 bool zlib::isAvailable() { return false; }
 void zlib::compress(StringRef InputBuffer,
@@ -103,7 +99,4 @@
                        size_t UncompressedSize) {
   llvm_unreachable("zlib::uncompress is unavailable");
 }
-uint32_t zlib::crc32(StringRef Buffer) {
-  llvm_unreachable("zlib::crc32 is unavailable");
-}
 #endif
Index: llvm/unittests/Support/CompressionTest.cpp
===================================================================
--- llvm/unittests/Support/CompressionTest.cpp
+++ llvm/unittests/Support/CompressionTest.cpp
@@ -64,12 +64,6 @@
   TestZlibCompression(BinaryDataStr, zlib::DefaultCompression);
 }
 
-TEST(CompressionTest, ZlibCRC32) {
-  EXPECT_EQ(
-      0x414FA339U,
-      zlib::crc32(StringRef("The quick brown fox jumps over the lazy dog")));
-}
-
 #endif
 
 }