Be consistent about deallocating memory allocated from C++ in C++

Fixes a crash on Windows due to mismatched allocators.

Author: DougGregor

include/swift/AST/ASTBridging.h

@@ -246,6 +246,9 @@ SWIFT_NAME("BridgedASTContext.langOptsGetCompilerVersion(self:_:)")
 SwiftInt BridgedASTContext_langOptsGetCompilerVersion(BridgedASTContext cContext,
                                                       SwiftInt* _Nullable * _Nonnull cComponents);
 
+/* Deallocate an array of Swift int values that was allocated in C++. */
+void deallocateIntBuffer(SwiftInt * _Nullable cComponents);
+
 enum ENUM_EXTENSIBILITY_ATTR(closed) BridgedCanImportVersion : size_t {
   CanImportUnversioned,
   CanImportVersion,

lib/AST/ASTBridging.cpp

@@ -195,6 +195,10 @@ namespace {
   }
 }
 
+void deallocateIntBuffer(SwiftInt * _Nullable cComponents) {
+  free(cComponents);
+}
+
 SwiftInt BridgedASTContext_langOptsGetLanguageVersion(BridgedASTContext cContext,
                                                       SwiftInt** cComponents) {
   auto theVersion = cContext.unbridged().LangOpts.EffectiveLanguageVersion;

lib/ASTGen/Sources/ASTGen/CompilerBuildConfiguration.swift

@@ -123,7 +123,7 @@ final class CompilerBuildConfiguration: BuildConfiguration {
     var bitWidthsBuf: UnsafeMutablePointer<SwiftInt>? = nil
     let count = ctx.langOptsGetTargetAtomicBitWidths(&bitWidthsBuf)
     let bitWidths = Array(UnsafeMutableBufferPointer(start: bitWidthsBuf, count: count))
-    bitWidthsBuf?.deallocate()
+    deallocateIntBuffer(bitWidthsBuf);
     return bitWidths
   }
 
@@ -140,7 +140,7 @@ final class CompilerBuildConfiguration: BuildConfiguration {
     let version = VersionTuple(
       components: Array(UnsafeMutableBufferPointer(start: componentsBuf, count: count))
     )
-    componentsBuf?.deallocate()
+    deallocateIntBuffer(componentsBuf);
     return version
   }
 
@@ -150,7 +150,7 @@ final class CompilerBuildConfiguration: BuildConfiguration {
     let version = VersionTuple(
       components: Array(UnsafeMutableBufferPointer(start: componentsBuf, count: count))
     )
-    componentsBuf?.deallocate()
+    deallocateIntBuffer(componentsBuf);
     return version
   }
 }