[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 -zone is obsolete in ARC.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
diff --git a/lib/ARCMigrate/Transforms.cpp b/lib/ARCMigrate/Transforms.cpp
index c584d6a..1d0e261 100644
--- a/lib/ARCMigrate/Transforms.cpp
+++ b/lib/ARCMigrate/Transforms.cpp
@@ -154,7 +154,8 @@
bool trans::isGlobalVar(Expr *E) {
E = E->IgnoreParenCasts();
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
- return DRE->getDecl()->getDeclContext()->isFileContext();
+ return DRE->getDecl()->getDeclContext()->isFileContext() &&
+ DRE->getDecl()->getLinkage() == ExternalLinkage;
if (ConditionalOperator *condOp = dyn_cast<ConditionalOperator>(E))
return isGlobalVar(condOp->getTrueExpr()) &&
isGlobalVar(condOp->getFalseExpr());
@@ -162,6 +163,13 @@
return false;
}
+StringRef trans::getNilString(ASTContext &Ctx) {
+ if (Ctx.Idents.get("nil").hasMacroDefinition())
+ return "nil";
+ else
+ return "0";
+}
+
namespace {
class ReferenceClear : public RecursiveASTVisitor<ReferenceClear> {