<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/85373>85373</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang][crash-on-valid] Crash in frontend with `std::source_location::current().column()` in deduction guide
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          LocalSpook
      </td>
    </tr>
</table>

<pre>
    The following code crashes Clang, compiling with `-std=c++20 -emit-llvm -Xclang -disable-llvm-passes`:

```cpp
#include <source_location>

template <int>
struct S { S(const char *); };

template <int M>
S(const char(&)[M]) -> S<std::source_location::current().column()>;

void f() {
    S{"If you remove this line, no crash happens."};
}
```

Link: https://godbolt.org/z/jPbb5Kr1P.
It does not crash on versions 17.1.0 and earlier.
I don't believe this is related to #67134, because this has a completely different backtrace.

It also gives an error:

```text
<source>:10:5: error: cannot compile this scalar expression yet
   10 |     S{"If you remove this line, no crash happens."};
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```

Backtrace:

```text
Stack dump:
0.      Program arguments: /opt/compiler-explorer/clang-trunk/bin/clang++ -gdwarf-4 -g -o /app/output.s -mllvm --x86-asm-syntax=intel -S --gcc-toolchain=/opt/compiler-explorer/gcc-snapshot -fcolor-diagnostics -fno-crash-diagnostics -std=c++20 -emit-llvm -Xclang -disable-llvm-passes <source>
1.      <eof> parser at end of file
2.      <source>:9:6: LLVM IR generation of declaration 'f'
3.      <source>:9:6: Generating code for declaration 'f'
 #0 0x00000000036774c8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x36774c8)
 #1 0x0000000003675614 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3675614)
 #2 0x00000000035bfc48 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #3 0x00007fbcd4242520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x0000000002f3a418 llvm::UndefValue::get(llvm::Type*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x2f3a418)
 #5 0x0000000003db06e6 (anonymous namespace)::ScalarExprEmitter::Visit(clang::Expr*) CGExprScalar.cpp:0:0
 #6 0x0000000003db2a53 clang::CodeGen::CodeGenFunction::EmitScalarExpr(clang::Expr const*, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3db2a53)
 #7 0x0000000003d53f9e clang::CodeGen::CodeGenFunction::EmitAnyExpr(clang::Expr const*, clang::CodeGen::AggValueSlot, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3d53f9e)
 #8 0x0000000003d6e83b clang::CodeGen::CodeGenFunction::EmitIgnoredExpr(clang::Expr const*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3d6e83b)
 #9 0x000000000397f0be clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x397f0be)
#10 0x0000000003985319 clang::CodeGen::CodeGenFunction::EmitCompoundStmtWithoutScope(clang::CompoundStmt const&, bool, clang::CodeGen::AggValueSlot) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3985319)
#11 0x00000000039e2fc4 clang::CodeGen::CodeGenFunction::EmitFunctionBody(clang::Stmt const*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x39e2fc4)
#12 0x00000000039ef422 clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x39ef422)
#13 0x0000000003a463bb clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a463bb)
#14 0x0000000003a42105 clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a42105)
#15 0x0000000003a42db0 clang::CodeGen::CodeGenModule::EmitGlobal(clang::GlobalDecl) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3a42db0)
#16 0x0000000003a4ae67 clang::CodeGen::CodeGenModule::EmitTopLevelDecl(clang::Decl*) (.part.0) CodeGenModule.cpp:0:0
#17 0x0000000003ecf3d6 (anonymous namespace)::CodeGeneratorImpl::HandleTopLevelDecl(clang::DeclGroupRef) ModuleBuilder.cpp:0:0
#18 0x0000000003ec04f9 clang::BackendConsumer::HandleTopLevelDecl(clang::DeclGroupRef) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3ec04f9)
#19 0x0000000005d7496c clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x5d7496c)
#20 0x0000000003ecce75 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3ecce75)
#21 0x0000000004162361 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4162361)
#22 0x00000000040e831b clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x40e831b)
#23 0x00000000042449a3 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x42449a3)
#24 0x0000000000c32d06 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc32d06)
#25 0x0000000000c2bb8d ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#26 0x0000000003f144f9 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::'lambda'()>(long) Job.cpp:0:0
#27 0x00000000035c0073 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x35c0073)
#28 0x0000000003f14719 clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (.part.0) Job.cpp:0:0
#29 0x0000000003edc457 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3edc457)
#30 0x0000000003edce0d clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3edce0d)
#31 0x0000000003ee6b6c clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3ee6b6c)
#32 0x0000000000c30121 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc30121)
#33 0x0000000000b26194 main (/opt/compiler-explorer/clang-trunk/bin/clang+++0xb26194)
#34 0x00007fbcd4229d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#35 0x00007fbcd4229e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#36 0x0000000000c2b36e _start (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc2b36e)
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzkWl1v2zzS_TXMDSFDor7si1w4dtI3z9tii7rb3TuDIimbTylSIKnU3ov97QtSsiO6TtoE2sUCG_QjpsjhOWdGMyPK2Bi-k4zdgvwO5Osb3Nm90rcfFcFi0yr1_aZS9Hj7dc9grYRQP7jcQaIog0Rjs2cGrgSWO4BWkKim5cJd_8HtHoIijoylIF0TgO4AukMxjFjDbSTEUwOjvxO3EEaUG1wJ5kejFhvDDChikC5BvAbx6d8i7v-Qth1GUMolER1lEKQrozpN2FYogi1XEqT349WWNa3A1s_k0p6vGqs7YuEGgvIObgCaEyWNhWSPNQRoCdACpHcQlGuQ3r1iD346WwyNADQHqHBm8rtPIF8DtIARSO_hxkF22ixBuvwJuxskndZMWm9hMSNKdI3sP7i9QjhPilNY91cdlX4UQgg37hNCjzU8qg5q1qgnBu2eGyi4ZM5pUvWOhHvctkyaGUAoIFyuLzww3vkjl99BuoR7a1vjgKMHgB52ilZK2JnSO4Ae_gHQw5-fqyr_f518nvXrHi2kihkolR22VxI-MW24kgYm5SyZxRBLChnWgjN9WgapkgCVFlZMcHbiwg3UzPmDQqsgQGlRJmnm2FWM4M4M0_bYQOyjVDDLxBFSXtfMqQwrTL5bjQmbjdk9WoiFUXDHn5iBWEKmtdIvRaZlBzsMneLRu2qZuGDOnUyn9ZBg6an7O2aAZwgWWEN2aDUzTgh4ZPbsyiSGoFzBaZzqzXh7IL__55t-XgmGu5OIv1ZoYzH5DmnXtOe58QzEi89a7TRuINa7rmHSupiCAD2o1gL0MMilI3ZohdJMuzGXRCKrO_kdoIeKy9NYn3NgtKM_sK6jDEY7GLnoeMBt60x2tu3szMCo6fNRdJgXETZNZI7S4gNI11xaJmC0gVG0IySySgmyx1yCdP0qJjfZSNyavbIwqokSSkeU451UxnJiYFRLFXkPhcPvTJcwCDivZuLUBOmKqdrlmxZrwzTEFjJJoaphzQXrZ6Jh5jhiFyBdFk76jx-_fYKPX-COSaZ9dnKLKSMCDx8BKmuAyt5W-pqtD4ONU_2olX7ZkruLYxgf4tNPWpRlRubQ0R7S5tH0v3zWXFofUV999KH58ySNf2yVsZrhxmfiFXT536VJly3fH1cA3cWHAZPLyWfQyQXovEiya6BXgmHZtX-RG76TWAA076SvxBQK5XaZDKJDEEBEAcS8qkk2hysXjV8YUU9MH3tM_4clFW6n-aBZMGelpLufZ64gp8vY_z1vkQ5blHVFaIYylKN44CN4BdDDYV5siywSXHaHaCe7_gKZGTUrPHC_JICdjWGjOsVZMg6Hv0rK6m9YdKz_vGM2iISvx5b1NX0SYQcAAcI8EJZWccEKtxmWSh4b1RkoccNM64N00cPa-Kx_f2j1fcOtZbof_sYNd_j7bf2QmzMQWH1wH_ql1x1QXEBBOE_hyNhKUfaByeDDQyfJcwPi4DyD-xkK9G2OB7SClVJispDt0QbKliGdPK0X7O10lvL4G1xeMrvc7Xx4bYSy03P2lALO85BzweZp9XbOjzupNKO_5D0VDw8z4LEIeCzKOq7e4buNbS7uBzcSOO75Xl9qjY9fWA3S1WjB0toR4_R-MtI9pzNpVwXC2rWY52myeDvplWpa1UnqqP6N273q7IYol8fmga3nWSd-xXOE_m5ETyWG5xqIEdbEBUM1yd4uxmnkTtHjq5EwFRGPMyCCLojUGUJvIzI0QcxdDEl8EKrCYs2ICGP5vP717LT6cJr4KGs1CoPJ1HBkAzXSQA2cFWn1ywT1SdFOsGen9qxP0Nes5pL3bH9Hm368L_oTer6nEnDNLriiJM7fx_W_hqOjEHDMLznSKn4fx5eZTYeeVnGAvrhAj1lRvhX9V9V-ZE9swDrm0I-c5J-1WNtZ7FuxsaWfezGHLGxeGKlT-su2cDDrcoXSj00r-uG-JX8d5getutYVP7SAPay7jgvKrnSKDt38Al2c1UGlck_1TNKVkqZrTu3pW3FM4vQeW-D0oLfIaZktCjIG_9k99y43Xy_qBWvwRYmcspkbcIyBovhCZcLKa_ljOa55B0Y6y4ah4XBvGh3d7gG8oEJnSYHSIhnDe9DuaU_SK_gmRDZsHCALSm4Ws3maXBSZfq9HaSyWhF3X7mUq05XIAVyAPiiRGcqyBQ4ewwaczySeTofAP3V4AcnpCsEAKkAdFLuYpIjGBSQk2TbY2Zhfb7T3-KK7XsFwDK3gk-J0QvA9tAB7HmJHVTWn8CTzKvnq7_MRg02DhfjGyDnNXiFShBXZ2RhOP4I-i2r-9EKWRWF1qpPMZVl_bv9stx66oK32gvqroyN__1YAC1Fh8n1by_DZpt97iJZVslJNgyW9vFGvOu78HkK1bnfsNBjpYzWXOz_zfvDqecF2Sw6HJOk_VNhwsjV--qBiMNkNbK3G3JrT5QtzWPhXIEqPrrspoxMGHzm95n4JQKXATUUxQOWzVGh-OkL7Q1XX_RHW5JzEcZmOXHHtpKu_8qWTG1wzcQzkfN11UyXuHmYQ7vPLuCrD58z_ubi4aM9eDIDwVIJRkuXli8J5h-GfSt9JzSBXXyx0E4KH8t-bugz6kxG3Ccq_5zqOoouTdkYJi-lbxfhDVeZlJf5Q1UduwuOJ15Lw2fkt5np4a_sG8YYI-TdKyGIaSBiecTBWVGEnOoa7Hv0edABXSv9L0v8HJZyq7fSaBKKhi0YjTtDQdp5ajRNonzWWPx30vVSKp2kuHJwAb9DOxRUqkkUGHdJJNuztBRtm4XsUtKCLN75H8UsCm_mlTZbFcLt1y7bGYm23I0a_vQvLwl2Kyz4sLRjs7U_jHW_xecvTO-YbepvSRbrAN-w2KZM4W2RxnN3sb2OKcpojUiwQY3mKsjItGV2UJS1oUaHkht-iGGVxmuTxIklRNosxrUvEalLQIiVkDrKYNZiLmYu_mdK7G25Mx27neVqmNwJXTBj_NRqEBrQI5Osbfetf1VbdzoAsFtxY82zBciv8d2_6Ffna_epfDCsZPWHBKcjX_Ys3yCWsh4eX8zds3v0lkiJ29iijnW9c4K7jlN10WtxefJeD231XzYhqnNPdjdf_F7Va_cmIc6FXwQD04IX4VwAAAP__5dDrSg">