[arcmt] More automatic transformations and safety improvements; rdar://9615812 :

- Replace calling -zone with 'nil'. -zone is obsolete in ARC.
- Allow removing retain/release on a static global var.
- Fix assertion hit when scanning for name references outside a NSAutoreleasePool scope.
- Automatically add bridged casts for results of objc method calls and when calling CFRetain, for example:

NSString *s;
CFStringRef ref = [s string];   -> CFStringRef ref = (__bridge CFStringRef)([s string]);
ref = s.string;                 -> ref = (__bridge CFStringRef)(s.string);
ref = [NSString new];           -> ref = (__bridge_retained CFStringRef)([NSString new]);
ref = [s newString];            -> ref = (__bridge_retained CFStringRef)([s newString]);
ref = [[NSString alloc] init];  -> ref = (__bridge_retained CFStringRef)([[NSString alloc] init]);
ref = [[s string] retain];      -> ref = (__bridge_retained CFStringRef)([s string]);
ref = CFRetain(s);              -> ref = (__bridge_retained CFTypeRef)(s);
ref = [s retain];               -> ref = (__bridge_retained CFStringRef)(s);

- Emit migrator error when trying to cast to CF type the result of autorelease/release:
  for

CFStringRef f3() {
  return (CFStringRef)[[[NSString alloc] init] autorelease];
}

emits:

t.m:12:10: error: [rewriter] it is not safe to cast to 'CFStringRef' the result of 'autorelease' message; a __bridge cast may result in a pointer to a destroyed object and a __bridge_retained may leak the object
  return (CFStringRef)[[[NSString alloc] init] autorelease];
         ^            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
t.m:12:3: note: [rewriter] remove the cast and change return type of function to 'NSString *' to have the object automatically autoreleased
  return (CFStringRef)[[[NSString alloc] init] autorelease];
  ^

- Before changing attributes to weak/unsafe_unretained, check if the backing ivar
  is set to a +1 object, in which case use 'strong' instead.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@136208 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 0 deletions

diff --git a/test/ARCMT/nonobjc-to-objc-cast.m b/test/ARCMT/nonobjc-to-objc-cast.m
index 4e1e293efb..b4e4080149 100644
--- a/test/ARCMT/nonobjc-to-objc-cast.m
+++ b/test/ARCMT/nonobjc-to-objc-cast.m
@@ -5,6 +5,8 @@
 #include "Common.h"
 
 @interface NSString : NSObject
+-(id)string;
+-(id)newString;
 @end
 
 typedef const struct __CFString * CFStringRef;
@@ -27,6 +29,7 @@ void f(BOOL b, id p) {
   CFUUIDRef   _uuid;
   NSString *_uuidString = (NSString *)CFUUIDCreateString(kCFAllocatorDefault, _uuid);
   _uuidString = [(NSString *)CFUUIDCreateString(kCFAllocatorDefault, _uuid) autorelease];
+  _uuidString = CFRetain(_uuid);
 }
 
 @implementation NSString (StrExt)
@@ -36,3 +39,18 @@ void f(BOOL b, id p) {
   return self;
 }
 @end
+
+void f2(NSString *s) {
+  CFStringRef ref = [s string];
+  ref = (CFStringRef)[s string];
+  ref = s.string;
+  ref = [NSString new];
+  ref = [s newString];
+  ref = (CFStringRef)[NSString new];
+  ref = [[NSString alloc] init];
+  ref = [[s string] retain];
+  ref = CFRetain((CFStringRef)[s string]);
+  ref = CFRetain([s string]);
+  ref = CFRetain(s);
+  ref = [s retain];
+}