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<p class="MsoNormal"><span lang="EN-US">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I was trying to use __attribute__((overloadable)) for functions accepting enumerated types but hadn’t succeeded so far.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Clang 3.1 and 3.2 failed to compile the following example.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-indent:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">/* clang -x c foo.cpp */<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">typedef enum __One {DUMMY_1} One;<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">typedef enum {DUMMY_2} Two;<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">enum Three {DUMMY_3};<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">__attribute__((overloadable)) void foo(One);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">__attribute__((overloadable)) void foo(Two);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">__attribute__((overloadable)) void foo(enum Three);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">int main()<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">{<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> foo(DUMMY_1);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> return 0;<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">}
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Providing me with the following error message:<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">$ clang -x c foo.cpp<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">foo.cpp:22:3: error: call to 'foo' is ambiguous<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> foo(DUMMY_1);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> ^~~<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">foo.cpp:16:36: note: candidate function<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">__attribute__((overloadable)) void foo(One);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> ^<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">foo.cpp:17:36: note: candidate function<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">__attribute__((overloadable)) void foo(Two);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> ^<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">foo.cpp:18:36: note: candidate function<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">__attribute__((overloadable)) void foo(enum Three);<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New""> ^<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US" style="font-family:"Courier New"">1 error generated.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">While with “-x c++” both versions of Clang compiled it successfully (failed to link though).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">According to </span><a href="http://clang.llvm.org/docs/LanguageExtensions.html#function-overloading-in-c"><span lang="EN-US">http://clang.llvm.org/docs/LanguageExtensions.html#function-overloading-in-c</span></a><span lang="EN-US">
overloadable attribute is an analogue for C++ function overloading in C.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">So, is it a bug in the Clang or I didn’t understand/consider something?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:16.0pt;font-family:"Brush Script MT";color:#7030A0;mso-fareast-language:RU">BR,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:16.0pt;font-family:"Brush Script MT";color:#7030A0;mso-fareast-language:RU">Andrey Lizunov<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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