<html>
<head>
<base href="https://llvm.org/bugs/" />
</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 --- - Fail to link instantiation of basic_regex with a custom character type"
href="https://llvm.org/bugs/show_bug.cgi?id=31409">31409</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Fail to link instantiation of basic_regex with a custom character type
</td>
</tr>
<tr>
<th>Product</th>
<td>libc++
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</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>All Bugs
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>karen@codesynthesis.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org, mclow.lists@gmail.com
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>Trying to instantiate std::basic_regex template with a custom character type
results in a linker error like this:
driver.o:(.rodata._ZTVNSt3__123__match_any_but_newlineIN6build24test6script5regex9line_charEEE[_ZTVNSt3__123__match_any_but_newlineIN6build24test6script5regex9line_charEEE]+0x20):
undefined reference to
`std::__1::__match_any_but_newline<build2::test::script::regex::line_char>::__exec(std::__1::__state<build2::test::script::regex::line_char>&)
const'
That happens as libc++ only provides specialization of
__match_any_but_newline::__exec() for char and wchar_t types, and lacks
implementation which would be available for any other instantiation of the
__match_any_but_newline template.
Probably it would be right to assume that a custom character type can have no
notion of a newline character at all. As a real life example, in build2
toolchain we develop, such a character represents a line of a program output,
or an inner level regex matching such a line, or a syntax regex character.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>