Make the -disable-free flag more full featured (#136213)

This lets us pass `-no-disable-free` to re-enable freeing memory for
example. This is especially helpful for library users of Clang where it
is important to not slowly leak memory.

Author: chandlerc

clang/include/clang/Driver/Options.td

@@ -7889,9 +7889,13 @@ def code_completion_with_fixits : Flag<["-"], "code-completion-with-fixits">,
 def skip_function_bodies : Flag<["-"], "skip-function-bodies">,
   HelpText<"Skip function bodies when possible">,
   MarshallingInfoFlag<FrontendOpts<"SkipFunctionBodies">>;
-def disable_free : Flag<["-"], "disable-free">,
-  HelpText<"Disable freeing of memory on exit">,
-  MarshallingInfoFlag<FrontendOpts<"DisableFree">>;
+defm disable_free : BoolOption<"",
+  "disable-free",
+  FrontendOpts<"DisableFree">,
+  DefaultFalse,
+  PosFlag<SetTrue, [], [ClangOption], "Disable">,
+  NegFlag<SetFalse, [], [ClangOption], "Don't disable">,
+  BothFlags<[], [ClangOption], " freeing of memory on exit">>;
 defm clear_ast_before_backend : BoolOption<"",
   "clear-ast-before-backend",
   CodeGenOpts<"ClearASTBeforeBackend">,

clang/test/Driver/clang-translation.c

@@ -10,6 +10,10 @@
 // I386: "-o"
 // I386: clang-translation
 
+// RUN: %clang -target i386-unknown-unknown -### -S %s -o %t.s -Xclang -no-disable-free 2>&1 | FileCheck -check-prefix=FREE %s
+// FREE: "-disable-free"
+// FREE: "-no-disable-free"
+
 // RUN: %clang -target i386-unknown-unknown -### -S %s -fasynchronous-unwind-tables -fno-unwind-tables 2>&1 | FileCheck --check-prefix=UNWIND-TABLES %s --implicit-check-not=warning:
 // UNWIND-TABLES: "-funwind-tables=2"