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<base href="https://llvm.org/bugs/" />
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<body><table border="1" cellspacing="0" cellpadding="8">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - [ms] Poor diagnostic when having __declspec and __attribute__ in the wrong order"
href="https://llvm.org/bugs/show_bug.cgi?id=24925">24925</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>[ms] Poor diagnostic when having __declspec and __attribute__ in the wrong order
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>All
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Frontend
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>nicolasweber@gmx.de
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>$ cat test2.cc
class __declspec(dllexport)
__attribute__((annotate("blink_gc_plugin_ignore"))) Foo {};
$ bin/clang-cl -c test2.cc
test2.cc(1,1) : error: declaration of anonymous class must be a definition
class __declspec(dllexport)
^
test2.cc(1,1) : warning: declaration does not declare anything
[-Wmissing-declarations]
class __declspec(dllexport)
^
1 warning and 1 error generated.
In real life, this causes several cascading errors [1]. We should detect this
and say "__declspec must come before __attribute__" or something like that. (Or
we could allow interleaving declspecs and attributes – these are usually hidden
behind macros, and having to know which macros happen to be declspecs and which
are attributes is a bit annoying. On the other hand, it's nice that this
enforces a consistent ordering. On the third hand, this consistent ordering
isn't enforced if you have two attribute-based macros or two declspec-based
ones)
1: The diagnostic we got on our bots:
FAILED: ninja -t msvc -e environment.x86 --
"..\..\third_party/llvm-build/Release+Asserts/bin/clang-cl" -m32 /nologo
/showIncludes /FC
@obj\third_party\WebKit\Source\core\animation\webcore_shared.DeferredLegacyStyleInterpolation.obj.rsp
/c
..\..\third_party\WebKit\Source\core\animation\DeferredLegacyStyleInterpolation.cpp
/Foobj\third_party\WebKit\Source\core\animation\webcore_shared.DeferredLegacyStyleInterpolation.obj
/Fdobj\third_party\WebKit\Source\core\webcore_shared.cc.pdb
In file included from
..\..\third_party\WebKit\Source\core\animation\DeferredLegacyStyleInterpolation.cpp:10:
..\..\third_party\WebKit\Source\core/css/CSSBasicShapeValue.h(46,1) : error:
declaration of anonymous class must be a definition
class CORE_EXPORT GC_PLUGIN_IGNORE("535448") CSSBasicShapeValue : public
CSSValue {
^
..\..\third_party\WebKit\Source\core/css/CSSBasicShapeValue.h(46,1) : error:
declaration does not declare anything [-Werror,-Wmissing-declarations]
class CORE_EXPORT GC_PLUGIN_IGNORE("535448") CSSBasicShapeValue : public
CSSValue {
^
..\..\third_party\WebKit\Source\core/css/CSSBasicShapeValue.h(78,47) : error:
base class has incomplete type
class CSSBasicShapeCircleValue final : public CSSBasicShapeValue {
~~~~~~~^~~~~~~~~~~~~~~~~~
..\..\third_party\WebKit\Source\core/animation/DeferredLegacyStyleInterpolation.h(15,7)
: note: forward declaration of 'blink::CSSBasicShapeValue'
class CSSBasicShapeValue;
^</pre>
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