diff --git a/clang/include/clang/Support/Compiler.h b/clang/include/clang/Support/Compiler.h
index 5a74f8e3b6723..e1ae3eda4ccc2 100644
--- a/clang/include/clang/Support/Compiler.h
+++ b/clang/include/clang/Support/Compiler.h
@@ -50,7 +50,7 @@
 #define CLANG_EXPORT_TEMPLATE
 #endif
 #elif defined(__ELF__) || defined(__MINGW32__) || defined(_AIX) ||             \
-    defined(__MVS__)
+    defined(__MVS__) || defined(__CYGWIN__)
 #define CLANG_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define CLANG_TEMPLATE_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define CLANG_EXPORT_TEMPLATE
diff --git a/clang/tools/CMakeLists.txt b/clang/tools/CMakeLists.txt
index 9634eb12080c8..50e3d694236ac 100644
--- a/clang/tools/CMakeLists.txt
+++ b/clang/tools/CMakeLists.txt
@@ -26,9 +26,10 @@ endif()
 add_clang_subdirectory(c-index-test)
 
 add_clang_subdirectory(clang-refactor)
-# For MinGW we only enable shared library if LLVM_LINK_LLVM_DYLIB=ON.
+# For MinGW/Cygwin we only enable shared library if LLVM_LINK_LLVM_DYLIB=ON.
 # Without that option resulting library is too close to 2^16 DLL exports limit.
-if(UNIX OR (MSVC AND LLVM_BUILD_LLVM_DYLIB_VIS) OR (MINGW AND LLVM_LINK_LLVM_DYLIB))
+if((UNIX AND NOT CYGWIN) OR (MSVC AND LLVM_BUILD_LLVM_DYLIB_VIS) OR
+  ((MINGW OR CYGWIN) AND LLVM_LINK_LLVM_DYLIB))
   add_clang_subdirectory(clang-shlib)
 endif()
 
diff --git a/clang/tools/libclang/CIndexer.cpp b/clang/tools/libclang/CIndexer.cpp
index 12d9d418dea51..11d9312b64849 100644
--- a/clang/tools/libclang/CIndexer.cpp
+++ b/clang/tools/libclang/CIndexer.cpp
@@ -26,12 +26,6 @@
 #include <cstdio>
 #include <mutex>
 
-#ifdef __CYGWIN__
-#include <cygwin/version.h>
-#include <sys/cygwin.h>
-#define _WIN32 1
-#endif
-
 #ifdef _WIN32
 #include <windows.h>
 #elif defined(_AIX)
@@ -112,16 +106,6 @@ const std::string &CIndexer::getClangResourcesPath() {
                sizeof(mbi));
   GetModuleFileNameA((HINSTANCE)mbi.AllocationBase, path, MAX_PATH);
 
-#ifdef __CYGWIN__
-  char w32path[MAX_PATH];
-  strcpy(w32path, path);
-#if CYGWIN_VERSION_API_MAJOR > 0 || CYGWIN_VERSION_API_MINOR >= 181
-  cygwin_conv_path(CCP_WIN_A_TO_POSIX, w32path, path, MAX_PATH);
-#else
-  cygwin_conv_to_full_posix_path(w32path, path);
-#endif
-#endif
-
   LibClangPath += path;
 #elif defined(_AIX)
   getClangResourcesPathImplAIX(LibClangPath);
diff --git a/clang/tools/libclang/CMakeLists.txt b/clang/tools/libclang/CMakeLists.txt
index 299c14660f3d4..37a939ffcada7 100644
--- a/clang/tools/libclang/CMakeLists.txt
+++ b/clang/tools/libclang/CMakeLists.txt
@@ -106,7 +106,8 @@ if (LLVM_EXPORTED_SYMBOL_FILE)
                      DEPENDS ${LIBCLANG_VERSION_SCRIPT_FILE})
 endif()
 
-if(LLVM_ENABLE_PIC OR (WIN32 AND NOT LIBCLANG_BUILD_STATIC))
+if((NOT (WIN32 OR CYGWIN) AND LLVM_ENABLE_PIC) OR
+  ((WIN32 OR CYGWIN) AND NOT LIBCLANG_BUILD_STATIC))
   set(ENABLE_SHARED SHARED)
 endif()
 
diff --git a/llvm/lib/Support/Unix/Signals.inc b/llvm/lib/Support/Unix/Signals.inc
index 30e5f40193974..691e1014f18e8 100644
--- a/llvm/lib/Support/Unix/Signals.inc
+++ b/llvm/lib/Support/Unix/Signals.inc
@@ -847,7 +847,7 @@ void llvm::sys::PrintStackTrace(raw_ostream &OS, int Depth) {
 
     const char *name = strrchr(dlinfo.dli_fname, '/');
     if (!name)
-      OS << format(" %-*s", width, dlinfo.dli_fname);
+      OS << format(" %-*s", width, static_cast<const char *>(dlinfo.dli_fname));
     else
       OS << format(" %-*s", width, name + 1);