[cmake] Build Swift host libraries with -DCLANG_BUILD_STATIC on Windows

By default (`CLANG_BUILD_STATIC` and `CLANG_EXPORTS` not defined) some
Clang visibility macros expand to `__declspec(dllimport)`. Swift depends
on Clang statically, so needs to turn these macros off.

Author: AnthonyLatsis

cmake/modules/AddSwift.cmake

@@ -269,6 +269,16 @@ function(_add_host_variant_c_compile_flags target)
       target_compile_options(${target} PRIVATE
         $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:-U_DEBUG>)
     endif()
+
+    # Swift host libraries are always linked with Clang libraries statically,
+    # so turn off Clang visibility macros for both the library and its
+    # consumers.
+    #target_compile_definitions(${target} PUBLIC
+    #  $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:CLANG_BUILD_STATIC>)
+    #if(TARGET "obj.${target}")
+    #  target_compile_definitions("obj.${target}" PUBLIC
+    #    $<$<COMPILE_LANGUAGE:C,CXX,OBJC,OBJCXX>:CLANG_BUILD_STATIC>)
+    #endif()
   endif()
 
   if(SWIFT_HOST_VARIANT_SDK STREQUAL "ANDROID")

include/swift/APIDigester/ModuleAnalyzerNodes.h

@@ -17,11 +17,6 @@
 #ifndef __SWIFT_ABI_DIGESTER_MODULE_NODES_H__
 #define __SWIFT_ABI_DIGESTER_MODULE_NODES_H__
 
-#include "clang/AST/ASTContext.h"
-#include "clang/AST/DeclObjC.h"
-#include "clang/Lex/Preprocessor.h"
-#include "clang/Sema/Lookup.h"
-#include "clang/Sema/Sema.h"
 #include "llvm/ADT/TinyPtrVector.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/CommandLine.h"

lib/APIDigester/CMakeLists.txt

@@ -7,4 +7,10 @@ add_swift_host_library(swiftAPIDigester STATIC
 target_link_libraries(swiftAPIDigester PRIVATE
   swiftIDE)
 
+# Clang dependencies. These are private because APIDigester's public
+# interface does not use Clang symbols.
+target_link_libraries(swiftAPIDigester PRIVATE
+  clangAST
+  clangLex)
+
 set_swift_llvm_is_available(swiftAPIDigester)

lib/APIDigester/ModuleAnalyzerNodes.cpp

@@ -3,6 +3,8 @@
 #include "swift/Basic/Defer.h"
 #include "swift/Parse/Lexer.h"
 #include "swift/Sema/IDETypeChecking.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/Lex/Preprocessor.h"
 #include "llvm/ADT/STLExtras.h"
 #include <algorithm>
 #include <swift/APIDigester/ModuleAnalyzerNodes.h>

lib/IDE/CMakeLists.txt

@@ -46,6 +46,14 @@ target_link_libraries(swiftIDE PRIVATE
   swiftParse
   swiftSema)
 
+# Clang dependencies. These are private because IDE's public
+# interface does not use Clang symbols.
+target_link_libraries(swiftIDE PRIVATE
+  clangAST
+  clangBasic
+  clangIndex
+  clangLex)
+
 if (SWIFT_BUILD_SWIFT_SYNTAX)
   target_link_libraries(swiftIDE PRIVATE
     swiftIDEUtilsBridging