Commit Graph

11 Commits

Author SHA1 Message Date
Argyrios Kyrtzidis 9390747349 [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 -zone is obsolete in ARC.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.

llvm-svn: 136208
2011-07-27 05:28:18 +00:00
Chris Lattner 0e62c1cc0b remove unneeded llvm:: namespace qualifiers on some core types now that LLVM.h imports
them into the clang namespace.

llvm-svn: 135852
2011-07-23 10:55:15 +00:00
Argyrios Kyrtzidis a6fe4bfdf5 [arcmt] It's not safe to remove the -release on "[[someivar delegate] release];" since it's very likely
that, after migration, the object that was passed to 'setDelegate:' will not be properly retained, e.g:

-whatever {
  id x = [[MyDoHicky alloc] init];
  [someivar setDelegate: x]; // x won't get retained in ARC.
}
-dealloc {
  [[someivar delegate] release]; // give migration error here.
}

rdar://8858009

llvm-svn: 135327
2011-07-15 23:48:56 +00:00
Argyrios Kyrtzidis f59daff52e [arcmt] Rewrite to "foo = nil;" not "foo = 0;", as suggested by Jordy.
llvm-svn: 135309
2011-07-15 22:04:00 +00:00
Argyrios Kyrtzidis 6a8a14d217 [arcmt] For:
id x = ...
@try {
 ...
} @finally {
 [x release];
}

Migrator will drop the release. It's better to change it to "x = 0" in a @finally to avoid leak when exception is thrown.

rdar://9398256

llvm-svn: 135301
2011-07-15 21:11:23 +00:00
Argyrios Kyrtzidis f2a27f40d6 [arcmt] Don't remove retains/releases on a global variable, flag them with errors. rdar://9402555.
llvm-svn: 135213
2011-07-14 23:32:04 +00:00
Argyrios Kyrtzidis 08903e4c16 [arcmt] Allow -retain of an __unsafe_unretained receiver if the result gets used.
Keep the error if the result is unused. rdar://9552694.

llvm-svn: 135209
2011-07-14 22:46:12 +00:00
Argyrios Kyrtzidis 84b528f3b1 [arcmt] Emit an error for unused -autorelease messages.
An unused autorelease is badness. If we remove it the receiver
will likely die immediately while previously it was kept alive
by the autorelease pool. This is bad practice in general, so leave it
and emit an error to force the user to restructure his code.

rdar://9599884

llvm-svn: 135193
2011-07-14 21:26:49 +00:00
John McCall 4db5c3c83a In ARC, reclaim all return values of retainable type, not just those
where we have an immediate need of a retained value.

As an exception, don't do this when the call is made as the immediate
operand of a __bridge retain.  This is more in the way of a workaround
than an actual guarantee, so it's acceptable to be brittle here.

rdar://problem/9504800

llvm-svn: 134605
2011-07-07 06:58:02 +00:00
Argyrios Kyrtzidis 0b2bd862ff [arcmt] Fully migrate ObjC++ classes, rdar://9660007.
llvm-svn: 133763
2011-06-23 21:21:33 +00:00
Argyrios Kyrtzidis e5b475c688 [arcmt] Break apart Transforms.cpp.
llvm-svn: 133539
2011-06-21 20:20:39 +00:00