Commit Graph

12 Commits

Author SHA1 Message Date
Jordan Rose 06dd406e27 Add fix-it notes to the nullability consistency warning.
This is especially important for arrays, since no one knows the proper
syntax for putting qualifiers in arrays.

    nullability.h:3:26: warning: array parameter is missing a nullability type specifier (_Nonnull, _Nullable, or _Null_unspecified)
    void arrayParameter(int x[]);
                             ^
    nullability.h:3:26: note: insert '_Nullable' if the array parameter may be null
    void arrayParameter(int x[]);
                             ^
                              _Nullable
    nullability.h:3:26: note: insert '_Nonnull' if the array parameter should never be null
    void arrayParameter(int x[]);
                             ^
                              _Nonnull

rdar://problem/29524992

llvm-svn: 290132
2016-12-19 20:58:20 +00:00
Jordan Rose 16d52a2a72 Don't require nullability on 'va_list'.
There are many non-portable typedefs, but va_list is one that nobody
ever thinks of as a pointer or an array. (When's the last time you saw
someone check for a NULL va_list?) Make an exception for this one
special type.

Part of rdar://problem/25846421.

llvm-svn: 286522
2016-11-10 23:28:34 +00:00
Jordan Rose f85a9b06b8 Add -Wnullability-completeness-on-arrays.
This is an addition to (and sub-warning of) -Wnullability-completeness
that warns when an array parameter is missing nullability. When the
specific warning is switched off, the compiler falls back to only
warning on pointer types written as pointer types.

Note that use of nullability /within/ an array triggers the
completeness checks regardless of whether or not the array-specific
warning is enabled; the intent there is simply to determine whether a
particular header is trying to be nullability-aware at all.

Part of rdar://problem/25846421.

llvm-svn: 286520
2016-11-10 23:28:26 +00:00
Jordan Rose ce65364afc Don't require nullability on template parameters in typedefs.
Previously the following code would warn on the use of "T":

  template <typename T>
  struct X {
    typedef T *type;
  };

...because nullability is /allowed/ on template parameters (because
they could be pointers). (Actually putting nullability on this use of
'T' will of course break if the argument is a non-pointer type.)

This fix doesn't handle the case where a template parameter is used
/outside/ of a typedef. That seems trickier, especially in parameter
position.

llvm-svn: 285856
2016-11-02 20:44:07 +00:00
Douglas Gregor d4f2afa23c Fix inference of _Nullable for weak Objective-C properties.
The inference of _Nullable for weak Objective-C properties was broken
in several ways:

* It was back-patching the type information very late in the process
  of checking the attributes for an Objective-C property, which is
  just wrong.
* It was using ad hoc checks to try to suppress the warning about
  missing nullability specifiers (-Wnullability-completeness), which
  didn't actual work in all cases (rdar://problem/22985457)
* It was inferring _Nullable even outside of assumes-nonnull regions,
  which is wrong.

Putting the inference of _Nullable for weak Objective-C properties in
the same place as all of the other inference logic fixes all of these
ills.

llvm-svn: 249896
2015-10-09 20:36:17 +00:00
Douglas Gregor e83b95641f Substitute type arguments into uses of Objective-C interface members.
When messaging a method that was defined in an Objective-C class (or
category or extension thereof) that has type parameters, substitute
the type arguments for those type parameters. Similarly, substitute
into property accesses, instance variables, and other references.

This includes general infrastructure for substituting the type
arguments associated with an ObjCObject(Pointer)Type into a type
referenced within a particular context, handling all of the
substitutions required to deal with (e.g.) inheritance involving
parameterized classes. In cases where no type arguments are available
(e.g., because we're messaging via some unspecialized type, id, etc.),
we substitute in the type bounds for the type parameters instead.

Example:

  @interface NSSet<T : id<NSCopying>> : NSObject <NSCopying>
  - (T)firstObject;
  @end

  void f(NSSet<NSString *> *stringSet, NSSet *anySet) {
    [stringSet firstObject]; // produces NSString*
    [anySet firstObject]; // produces id<NSCopying> (the bound)
  }

When substituting for the type parameters given an unspecialized
context (i.e., no specific type arguments were given), substituting
the type bounds unconditionally produces type signatures that are too
strong compared to the pre-generics signatures. Instead, use the
following rule:

  - In covariant positions, such as method return types, replace type
    parameters with “id” or “Class” (the latter only when the type
    parameter bound is “Class” or qualified class, e.g,
    “Class<NSCopying>”)
  - In other positions (e.g., parameter types), replace type
    parameters with their type bounds.
  - When a specialized Objective-C object or object pointer type
    contains a type parameter in its type arguments (e.g.,
    NSArray<T>*, but not NSArray<NSString *> *), replace the entire
    object/object pointer type with its unspecialized version (e.g.,
    NSArray *).

llvm-svn: 241543
2015-07-07 03:57:53 +00:00
Douglas Gregor aea7afdc13 Replace __double_underscored type nullability qualifiers with _Uppercase_underscored
Addresses a conflict with glibc's __nonnull macro by renaming the type
nullability qualifiers as follows:

  __nonnull -> _Nonnull
  __nullable -> _Nullable
  __null_unspecified -> _Null_unspecified

This is the major part of rdar://problem/21530726, but does not yet
provide the Darwin-specific behavior for the old names.

llvm-svn: 240596
2015-06-24 22:02:08 +00:00
Douglas Gregor 227fe4bc03 Make -Wnullability-completeness work with -Wsystem-headers.
rdar://problem/21134250

llvm-svn: 240187
2015-06-19 23:17:55 +00:00
Douglas Gregor 9960a8638d CF_RETURNS_[NOT_]RETAINED on a param makes the inner pointer __nullable.
That is,

  void cf2(CFTypeRef * __nullable p CF_RETURNS_NOT_RETAINED);

is equivalent to

  void cf2(CFTypeRef __nullable * __nullable p CF_RETURNS_NOT_RETAINED);

More rdar://problem/18742441

llvm-svn: 240186
2015-06-19 23:17:51 +00:00
Douglas Gregor bec595a641 Check for consistent use of nullability type specifiers in a header.
Adds a new warning (under -Wnullability-completeness) that complains
about pointer, block pointer, or member pointer declarations that have
not been annotated with nullability information (directly or inferred)
within a header that contains some nullability annotations. This is
intended to be used to help maintain the completeness of nullability
information within a header that has already been audited.

Note that, for performance reasons, this warning will underrepresent
the number of non-annotated pointers in the case where more than one
pointer is seen before the first nullability type specifier, because
we're only tracking one piece of information per header. Part of
rdar://problem/18868820.

llvm-svn: 240158
2015-06-19 18:27:45 +00:00
Douglas Gregor 2a20bd1a94 Introduced pragmas for audited nullability regions.
Introduce the clang pragmas "assume_nonnull begin" and "assume_nonnull
end" in which we make default assumptions about the nullability of many
unannotated pointers:

  - Single-level pointers are inferred to __nonnull
  - NSError** in a (function or method) parameter list is inferred to
    NSError * __nullable * __nullable.
  - CFErrorRef * in a (function or method) parameter list is inferred
    to CFErrorRef __nullable * __nullable.
  - Other multi-level pointers are never inferred to anything.

Implements rdar://problem/19191042.

llvm-svn: 240156
2015-06-19 18:25:57 +00:00
John McCall 31168b077c Automatic Reference Counting.
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.

Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.

llvm-svn: 133103
2011-06-15 23:02:42 +00:00