<html>
<head>
<base href="https://bugs.llvm.org/">
</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 - Wrongsided function picked for overload when valid template function exists."
href="https://bugs.llvm.org/show_bug.cgi?id=46922">46922</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Wrongsided function picked for overload when valid template function exists.
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Keywords</th>
<td>compile-fail, regression
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>CUDA
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>canlewi@sandia.gov
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>The following code doesn’t compile with newer versions of clang:
template<class T>
__device__ __host__ int foo(T *x) {
return 1;
}
__device__ int foo(int *x) {
return 2;
}
__host__ int foo(long *x) {
return 3;
}
__device__ __host__ int bar() {
auto long_val = 1l;
return foo(&long_val);
}
clang++ -O2 -g -x cuda --cuda-gpu-arch=sm_61 -std=c++14 -o main -c main.cpp
give me:
error: reference to __host__ function 'foo' in __host__ __device__ function
return foo(&long_val);
^
main.cpp:10:14: note: 'foo' declared here
__host__ int foo(long *x) {
I believe that the issue is at
<a href="https://github.com/llvm/llvm-project/blob/8224c5047e9cef2db4b0e31427cdf90a2568a341/clang/lib/Sema/SemaOverload.cpp#L9860">https://github.com/llvm/llvm-project/blob/8224c5047e9cef2db4b0e31427cdf90a2568a341/clang/lib/Sema/SemaOverload.cpp#L9860</a>
It’s possible that IdentifyCUDAPreference will return CFP_HostDevice for valid
overloads, but this code doesn’t erase the wrong side candidates in that case.
Then best overload selection picks the wrong side candidate.
If I rewrite those lines as:
bool ContainsSameSideCandidate =
llvm::any_of(Candidates, [&](OverloadCandidate *Cand) {
// Check viable function only.
if (Cand->Viable && Cand->Function) {
auto MatchType = S.IdentifyCUDAPreference(Caller, Cand->Function);
return MatchType == Sema::CFP_HostDevice ||
MatchType == Sema::CFP_SameSide;
}
return false;
});
My code compiles again.</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>