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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua",serif;color:windowtext">Haha, 7 years. I tried with v4.0 and it was there too, but I did not look further back. Yes, the test case is contrived, but part of ANSI C89 validation.
I am not aware of any real-world-code that is still around that depends on this though.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua",serif;color:windowtext"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua",serif;color:windowtext">All the best,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua",serif;color:windowtext"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua",serif;color:windowtext"> MartinO<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua",serif;color:windowtext"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="color:windowtext;mso-fareast-language:EN-IE">From:</span></b><span lang="EN-US" style="color:windowtext;mso-fareast-language:EN-IE"> Friedman, Eli [mailto:efriedma@codeaurora.org]
<br>
<b>Sent:</b> Wednesday, October 4, 2017 7:15 PM<br>
<b>To:</b> ORiordan, Martin <martin.oriordan@intel.com>; Clang Dev <cfe-dev@lists.llvm.org><br>
<b>Subject:</b> Re: [cfe-dev] Unexpected error when compiling for ANSI C89<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On 10/4/2017 3:47 AM, ORiordan, Martin via cfe-dev wrote:<span style="font-size:12.0pt;mso-fareast-language:EN-IE"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif">Hi CFE-Devs,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif">When I compile the following tiny test with ‘</span><span style="font-size:12.0pt;font-family:"Courier New"">-std=c89</span><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif">’
(‘</span><span style="font-size:12.0pt;font-family:"Courier New"">clang –std=c89 –c xxx.c</span><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif">’):</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New"">foo(x) {</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New""> return;</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New"">}</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif">I get the following error message:</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New"">xxx.c:2:3: error: non-void function 'foo' should return a value [-Wreturn-type]</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New""> return;</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New""> ^</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><span style="font-size:12.0pt;font-family:"Courier New"">1 error generated.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Book Antiqua ,serif",serif"> </span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-language:EN-IE"><br>
Looks like an oversight in <a href="https://reviews.llvm.org/rL108108">https://reviews.llvm.org/rL108108</a>; in C99, we want to default to an error, but C89 we shouldn't, as you've pointed out. See also
<a href="https://bugs.llvm.org/show_bug.cgi?id=12216">https://bugs.llvm.org//show_bug.cgi?id=12216</a>.<br>
<br>
That said, it's been like this for seven years... it seems like this isn't causing issues in practice.<br>
<br>
-Eli<br>
<br>
<o:p></o:p></span></p>
<pre>-- <o:p></o:p></pre>
<pre>Employee of Qualcomm Innovation Center, Inc.<o:p></o:p></pre>
<pre>Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project<o:p></o:p></pre>
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