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<base href="https://bugs.llvm.org/">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - std::tm type needs to be mangled as "::tm" on Solaris for g++ binary compat"
href="https://bugs.llvm.org/show_bug.cgi?id=33767">33767</a>
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<th>Summary</th>
<td>std::tm type needs to be mangled as "::tm" on Solaris for g++ binary compat
</td>
</tr>
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<th>Product</th>
<td>clang
</td>
</tr>
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<th>Version</th>
<td>unspecified
</td>
</tr>
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<th>Hardware</th>
<td>All
</td>
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<th>OS</th>
<td>Solaris
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
</tr>
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<th>Component</th>
<td>LLVM Codegen
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>Fedor.Sergeev@oracle.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
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<pre>g++ on Solaris has special mangling twist that makes it generate non-standard
mangling for std::tm, std::div_t, std::ldiv_t, std::lconv types.
W/o this twist clang fails to link with libstdc++ on testcases like this:
] cat no-tm.cc
#include <locale>
struct D : std::time_get<char> {};
int main() {
D var;
var.date_order();
}
] clang no-tm.cc
Undefined first referenced
symbol in file
_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE11do_get_timeES3_S3_RSt8ios_baseRSt12_Ios_IostatePSt2tm
/var/tmp/no-tm-e5c67b.o
_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE11do_get_dateES3_S3_RSt8ios_baseRSt12_Ios_IostatePSt2tm
/var/tmp/no-tm-e5c67b.o
_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE14do_get_weekdayES3_S3_RSt8ios_baseRSt12_Ios_IostatePSt2tm
/var/tmp/no-tm-e5c67b.o
_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE11do_get_yearES3_S3_RSt8ios_baseRSt12_Ios_IostatePSt2tm
/var/tmp/no-tm-e5c67b.o
_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE16do_get_monthnameES3_S3_RSt8ios_baseRSt12_Ios_IostatePSt2tm
/var/tmp/no-tm-e5c67b.o
ld: fatal: symbol referencing errors
clang-5.0: error: linker command failed with exit code 1 (use -v to see
invocation)
]
Basically any signature that includes either of the aforementioned types is
mangled differently than whats in libstdc++.
Namely, clang mangles std::tm as std::tm (surpise! :), while gcc does it as
::tm.
Say, first undefined symbol above:
] nm /usr/lib/libstdc++.so | grep
_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE11do_get_timeES3_S3_RSt8ios_baseRSt12_Ios_Iostate
[6646] | 533632| 276|FUNC |WEAK |0 |810
|_ZNKSt8time_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE11do_get_timeES3_S3_RSt8ios_baseRSt12_Ios_IostateP2tm
]
Notice 2tm vs St2tm difference at the tail of the mangled name.</pre>
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