<html>
    <head>
      <base href="https://bugs.llvm.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Regression where default template type parameters no longer reported"
   href="https://bugs.llvm.org/show_bug.cgi?id=32539">32539</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Regression where default template type parameters no longer reported
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>clang
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>enhancement
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>libclang
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedclangbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>nfitzgerald@mozilla.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>klimek@google.com, llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Given this test case with a template definition using a default template type
parameter:

```
template <typename T, typename U = int>
struct Foo {
    T t;
    U u;
};

static Foo<bool> bar;
```

In libclang 3.9, I get a cursor for `bar`'s template instantiation like this:

```
(
 kind = StructDecl
 spelling = "Foo"
 location = ./tests/headers/default-template-parameter.hpp:2:8
 is-definition? true
 is-declaration? true
 is-inlined-function? false
 usr = "c:@S@Foo>#b#I"
 number-of-template-args = 2

 specialized.kind = ClassTemplate
 specialized.spelling = "Foo"
 specialized.location = ./tests/headers/default-template-parameter.hpp:2:8
 specialized.is-definition? true
 specialized.is-declaration? true
 specialized.is-inlined-function? false
 specialized.template-kind = StructDecl
 specialized.usr = "c:@ST>2#T#T@Foo"

 type.kind = Record
 type.cconv = 100
 type.spelling = "Foo<bool, int>"
 type.number-of-template-args = 2
 type.is-variadic? false
)
```

Then, using `clang_Type_getNumTemplateArguments` and
`clang_Type_getTemplateArgumentAsType`, I get these template arguments:

```
Type(spelling: bool, kind: Bool)
Type(spelling: int, kind: Int)
```

In contrast, with libclang >= 4.0, I get only the explicit template argument,
not the default type:

```
Type(spelling: bool, kind: Bool)
```

Here is the result of bisection on the git monorepo:

```
1cd3d77b9a8e18878a1654eb14053732b616b073 is the first bad commit
commit 1cd3d77b9a8e18878a1654eb14053732b616b073
Author: Argyrios Kyrtzidis <<a href="mailto:akyrtzi@gmail.com">akyrtzi@gmail.com</a>>
Date:   Tue Nov 15 20:51:46 2016 +0000

    [libclang] Generalize clang_getNumTemplateArguments and
clang_getTemplateArgumentAsType to other kind of specializations.

    Patch by Emilio Cobos Ãlvarez!
    <a href="https://reviews.llvm.org/D26663">https://reviews.llvm.org/D26663</a>
```</pre>
        </div>
      </p>


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