[LLVM][Cygwin] Fix symbol visibility definition

Author: mati865

llvm/cmake/modules/AddLLVM.cmake

@@ -666,7 +666,7 @@ function(llvm_add_library name)
     # When building shared objects for each target there are some internal APIs
     # that are used across shared objects which we can't hide.
     if (LLVM_BUILD_LLVM_DYLIB_VIS AND NOT BUILD_SHARED_LIBS AND NOT APPLE AND
-        (NOT (WIN32 OR CYGWIN) OR (MINGW AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
+        (NOT (WIN32 OR CYGWIN) OR ((MINGW OR CYGWIN) AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
         NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX") AND
         NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
 

llvm/cmake/modules/HandleLLVMOptions.cmake

@@ -210,7 +210,7 @@ if( LLVM_REVERSE_ITERATION )
   set( LLVM_ENABLE_REVERSE_ITERATION 1 )
 endif()
 
-if(WIN32)
+if(WIN32 OR CYGWIN)
   set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
   if(CYGWIN)
     set(LLVM_ON_WIN32 0)
@@ -455,7 +455,7 @@ if( LLVM_ENABLE_PIC )
 endif()
 
 if((NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX")) AND
-   (NOT (WIN32 OR CYGWIN) OR (MINGW AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")))
+   (NOT (WIN32 OR CYGWIN) OR ((MINGW OR CYGWIN) AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")))
   # GCC for MinGW does nothing about -fvisibility-inlines-hidden, but warns
   # about use of the attributes. As long as we don't use the attributes (to
   # override the default) we shouldn't set the command line options either.

llvm/include/llvm/Support/Compiler.h

@@ -129,7 +129,7 @@
 #endif
 
 #if (!(defined(_WIN32) || defined(__CYGWIN__)) ||                              \
-     (defined(__MINGW32__) && defined(__clang__)))
+     ((defined(__MINGW32__) || defined(__CYGWIN__)) && defined(__clang__)))
 #define LLVM_LIBRARY_VISIBILITY LLVM_ATTRIBUTE_VISIBILITY_HIDDEN
 // Clang compilers older then 15 do not support gnu style attributes on
 // namespaces.
@@ -198,7 +198,7 @@
 #endif
 #define LLVM_ABI_EXPORT __declspec(dllexport)
 #elif defined(__ELF__) || defined(__MINGW32__) || defined(_AIX) ||             \
-    defined(__MVS__)
+    defined(__MVS__) || defined(__CYGWIN__)
 #define LLVM_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define LLVM_TEMPLATE_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define LLVM_EXPORT_TEMPLATE

llvm/lib/Target/CMakeLists.txt

@@ -23,7 +23,7 @@ add_llvm_component_library(LLVMTarget
 # When building shared objects for each target there are some internal APIs
 # that are used across shared objects which we can't hide.
 if (NOT BUILD_SHARED_LIBS AND NOT APPLE AND
-    (NOT (WIN32 OR CYGWIN) OR (MINGW AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
+    (NOT (WIN32 OR CYGWIN) OR ((MINGW OR CYGWIN) AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
     NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX") AND
     NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
   # Set default visibility to hidden, so we don't export all the Target classes

llvm/tools/llvm-shlib/CMakeLists.txt

@@ -57,11 +57,11 @@ if(LLVM_BUILD_LLVM_DYLIB)
     else()
       # GNU ld doesn't resolve symbols in the version script.
       set(LIB_NAMES -Wl,--whole-archive ${LIB_NAMES} -Wl,--no-whole-archive)
-      if (NOT LLVM_LINKER_IS_SOLARISLD AND NOT MINGW)
+      if (NOT LLVM_LINKER_IS_SOLARISLD AND NOT (MINGW OR CYGWIN))
         # Solaris ld does not accept global: *; so there is no way to version *all* global symbols
         set(LIB_NAMES -Wl,--version-script,${LLVM_LIBRARY_DIR}/tools/llvm-shlib/simple_version_script.map ${LIB_NAMES})
       endif()
-      if (NOT MINGW AND NOT LLVM_LINKER_IS_SOLARISLD_ILLUMOS)
+      if (NOT (MINGW OR CYGWIN) AND NOT LLVM_LINKER_IS_SOLARISLD_ILLUMOS)
         # Optimize function calls for default visibility definitions to avoid PLT and
         # reduce dynamic relocations.
         # Note: for -fno-pic default, the address of a function may be different from