Commit Graph

4 Commits

Author SHA1 Message Date
Douglas Gregor e1314a64b8 Switch the initialization required by return statements over to the
new InitializationSequence. This fixes some bugs (e.g., PR5808),
changed some diagnostics, and caused more churn than expected. What's
new:

  - InitializationSequence now has a "C conversion sequence" category
    and step kind, which falls back to
  - Changed the diagnostics for returns to always have the result type
    of the function first and the type of the expression second.
    CheckSingleAssignmentConstraints to peform checking in C. 
  - Improved ASTs for initialization of return values. The ASTs now
    capture all of the temporaries we need to create, but
    intentionally do not bind the tempoary that is actually returned,
    so that it won't get destroyed twice.
  - Make sure to perform an (elidable!) copy of the class object that
    is returned from a class.
  - Fix copy elision in CodeGen to properly see through the
    subexpressions that occur with elidable copies.
  - Give "new" its own entity kind; as with return values and thrown
    objects, we don't bind the expression so we don't call a
    destructor for it.

Note that, with this patch, I've broken returning move-only types in
C++0x. We'll fix it later, when we tackle NRVO.

llvm-svn: 91669
2009-12-18 05:02:21 +00:00
Daniel Dunbar 8fbe78f6fc Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'.
- This is designed to make it obvious that %clang_cc1 is a "test variable"
   which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
   can be useful to redefine what gets run as 'clang -cc1' (for example, to set
   a default target).

llvm-svn: 91446
2009-12-15 20:14:24 +00:00
Douglas Gregor 3e1e527826 Reimplement reference initialization (C++ [dcl.init.ref]) using the
new notion of an "initialization sequence", which encapsulates the
computation of the initialization sequence along with diagnostic
information and the capability to turn the computed sequence into an
expression. At present, I've only switched one CheckReferenceInit
callers over to this new mechanism; more will follow.

Aside from (hopefully) being much more true to the standard, the
diagnostics provided by this reference-initialization code are a bit
better than before. Some examples:

p5-var.cpp:54:12: error: non-const lvalue reference to type 'struct
Derived'
      cannot bind to a value of unrelated type 'struct Base'
  Derived &dr2 = b; // expected-error{{non-const lvalue reference to
  ...
           ^     ~
p5-var.cpp:55:9: error: binding of reference to type 'struct Base' to
a value of
      type 'struct Base const' drops qualifiers
  Base &br3 = bc; // expected-error{{drops qualifiers}}
        ^     ~~

p5-var.cpp:57:15: error: ambiguous conversion from derived class
      'struct Diamond' to base class 'struct Base':
    struct Diamond -> struct Derived -> struct Base
    struct Diamond -> struct Derived2 -> struct Base
  Base &br5 = diamond; // expected-error{{ambiguous conversion from
      ...
              ^~~~~~~
p5-var.cpp:59:9: error: non-const lvalue reference to type 'long'
      cannot bind to
      a value of unrelated type 'int'
  long &lr = i; // expected-error{{non-const lvalue reference to type
      ...
        ^    ~

p5-var.cpp:74:9: error: non-const lvalue reference to type 'struct
Base' cannot
      bind to a temporary of type 'struct Base'
  Base &br1 = Base(); // expected-error{{non-const lvalue reference to
  ...
        ^     ~~~~~~

p5-var.cpp:102:9: error: non-const reference cannot bind to bit-field
'i'
  int & ir1 = (ib.i); // expected-error{{non-const reference cannot
  ...
        ^     ~~~~~~
p5-var.cpp:98:7: note: bit-field is declared here
  int i : 17; // expected-note{{bit-field is declared here}}
      ^

llvm-svn: 90992
2009-12-09 23:02:17 +00:00
Fariborz Jahanian 31481d8b22 Handle ambiguity of reference initialization.
Removes a FIXME.

llvm-svn: 84068
2009-10-14 00:52:43 +00:00