thereof. Patch by Anders Johnsen!

llvm-svn: 73641

Implement support for C++ Substitution Failure Is Not An Error
(SFINAE), which says that errors that occur during template argument
deduction do *not* produce diagnostics and do not necessarily make a
program ill-formed. Instead, template argument deduction silently
fails. This is currently implemented for template argument deduction
during matching of class template partial specializations, although
the mechanism will also apply to template argument deduction for
function templates. The scheme is simple:

  - If we are in a template argument deduction context, any diagnostic
    that is considered a SFINAE error (or warning) will be
    suppressed. The error will be propagated up the call stack via the
    normal means.
  - By default, all warnings and errors are SFINAE errors. Add the
    NoSFINAE class to a diagnostic in the .td file to make it a hard
    error (e.g., for access-control violations).

Note that, to make this fully work, every place in Sema that emits an
error *and then immediately recovers* will need to check
Sema::isSFINAEContext() to determine whether it must immediately
return an error rather than recovering.

llvm-svn: 73332

Move a bunch of tests into temp.param, and write a few tests for paragraphs that hadn't been touched before

llvm-svn: 73288

I'm not completely sure this is the right way to fix this issue, but it seems 
reasonable, and it's consistent with the non-template code for this 
construct.

llvm-svn: 73285

If a CXXRecordDecl is a class template, the 'this' type should be the injected class name type. Fixes pr4383.

llvm-svn: 73284

llvm-svn: 73281

specialization cannot be deduced, produce a warning noting that the
affected class template partial specialization will never be used.

llvm-svn: 73274

llvm-svn: 73269

llvm-svn: 73267

llvm-svn: 73262

llvm-svn: 73260

specialization's arguments are identical to the implicit template
arguments of the primary template. Typically, this is meant to be a
declaration/definition of the primary template, so we give that
advice.

llvm-svn: 73259

template partial specializations.

llvm-svn: 73254

llvm-svn: 73247

specialization do not have default arguments 
(C++ [temp.class.spec]p10). 

llvm-svn: 73245

llvm-svn: 73240

llvm-svn: 73232

partial specialization, substitute those template arguments back into
the template arguments of the class template partial specialization to
see if the results still match the original template arguments.

This code is more general than it needs to be, since we don't yet
diagnose C++ [temp.class.spec]p9. However, it's likely to be needed
for function templates.

llvm-svn: 73196

Add a null check that fixes the crash in PR4362, and make sure to instantiate non-type template arguments.

llvm-svn: 73193

(Actually, this isn't precisely correct, but it doesn't make 
sense to query whether an expression that isn't an ICE is 
value-dependent anyway.)

llvm-svn: 73179

llvm-svn: 73178

Also, introduced some of the framework for performing instantiation as
part of template argument deduction.

llvm-svn: 73175

T::*) and implement template instantiation for member pointer types.

llvm-svn: 73151

llvm-svn: 73147

specialization types. As the example shows, we can now compute the
length of a type-list using a template metaprogram and class template
partial specialization.

llvm-svn: 73136

llvm-svn: 73077

llvm-svn: 73072

llvm-svn: 73070

Instantiation support for more Obj-C expressions, string literals, @selector and @protocol expressions.

llvm-svn: 73036

llvm-svn: 73034

llvm-svn: 72913

llvm-svn: 72911

  - Once we have deduced template arguments for a class template partial
    specialization, we use exactly those template arguments for instantiating
    the definition of the class template partial specialization.
  - Added template argument deduction for non-type template parameters.
  - Added template argument deduction for dependently-sized array types.

With these changes, we can now implement, e.g., the remove_reference
type trait. Also, Daniel's Ackermann template metaprogram now compiles
properly.

llvm-svn: 72909

llvm-svn: 72844

llvm-svn: 72822

deductions of the same template parameter are equivalent. This allows
us to implement the is_same type trait (!).

Also, move template argument deduction into its own file and update a
few build systems with this change (grrrr).

llvm-svn: 72819

llvm-svn: 72747

After spending 15 minutes trying to figure out why this was crashing, I realized it was a bug in the test case :)

llvm-svn: 72680

we have the basics of declaring and storing class template partial
specializations, matching class template partial specializations at
instantiation time via (limited) template argument deduction, and
using the class template partial specialization's pattern for
instantiation. 

This patch is enough to make a simple is_pointer type trait work, but
not much else.

llvm-svn: 72662

printing logic to help customize the output. For now, we use this
rather than a special flag to suppress the "struct" when printing
"struct X" and to print the Boolean type as "bool" in C++ but "_Bool"
in C.

llvm-svn: 72590