<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 --- - clang crashes on (valid?) code with inlined assembly: Assertion `CastInst::castIsValid(opc, C, Ty) && "Invalid constantexpr cast!"' failed"
href="https://llvm.org/bugs/show_bug.cgi?id=29066">29066</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>clang crashes on (valid?) code with inlined assembly: Assertion `CastInst::castIsValid(opc, C, Ty) && "Invalid constantexpr cast!"' failed
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</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>-New Bugs
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>su@cs.ucdavis.edu
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>This is a regression from 3.8.x, which accepts the code.
The code is rejected by GCC, however.
$ clang -v
clang version 4.0.0 (trunk 279116)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/local/clang-trunk/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/4.9
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/4.9.3
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5.3.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.4.7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.6.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.7.3
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.8.5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9.3
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.3.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.1.1
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@mx32
Selected multilib: .;@m64
$
$ clang-3.8 -c small.c
$
$ gcc-6.1 -c small.c
small.c: In function ‘foo’:
small.c:5:3: error: inconsistent operand constraints in an ‘asm’
__asm__ ("": "=t" (a):"0" (0));
^~~~~~~
$
$ clang -c small.c
clang-4.0: /tmp/llvm-builder/llvm-source-trunk/lib/IR/Constants.cpp:1462:
static llvm::Constant* llvm::ConstantExpr::getCast(unsigned int,
llvm::Constant*, llvm::Type*, bool): Assertion `CastInst::castIsValid(opc, C,
Ty) && "Invalid constantexpr cast!"' failed.
#0 0x0000000001de8dd5 llvm::sys::PrintStackTrace(llvm::raw_ostream&)
(/usr/local/clang-trunk/bin/clang-4.0+0x1de8dd5)
#1 0x0000000001de6ebe llvm::sys::RunSignalHandlers()
(/usr/local/clang-trunk/bin/clang-4.0+0x1de6ebe)
#2 0x0000000001de7020 SignalHandler(int)
(/usr/local/clang-trunk/bin/clang-4.0+0x1de7020)
#3 0x00007f8eeb2df340 __restore_rt
(/lib/x86_64-linux-gnu/libpthread.so.0+0x10340)
#4 0x00007f8eea0d0cc9 gsignal
/build/eglibc-3GlaMS/eglibc-2.19/signal/../nptl/sysdeps/unix/sysv/linux/raise.c:56:0
#5 0x00007f8eea0d40d8 abort
/build/eglibc-3GlaMS/eglibc-2.19/stdlib/abort.c:91:0
#6 0x00007f8eea0c9b86 __assert_fail_base
/build/eglibc-3GlaMS/eglibc-2.19/assert/assert.c:92:0
#7 0x00007f8eea0c9c32 (/lib/x86_64-linux-gnu/libc.so.6+0x2fc32)
#8 0x00000000019cf676 llvm::ConstantExpr::getCast(unsigned int,
llvm::Constant*, llvm::Type*, bool)
(/usr/local/clang-trunk/bin/clang-4.0+0x19cf676)
#9 0x0000000001f89b3d
clang::CodeGen::CodeGenFunction::EmitAsmStmt(clang::AsmStmt const&)
(/usr/local/clang-trunk/bin/clang-4.0+0x1f89b3d)
#10 0x0000000001f8f45f
clang::CodeGen::CodeGenFunction::EmitCompoundStmtWithoutScope(clang::CompoundStmt
const&, bool, clang::CodeGen::AggValueSlot)
(/usr/local/clang-trunk/bin/clang-4.0+0x1f8f45f)
#11 0x0000000001fb6422
clang::CodeGen::CodeGenFunction::EmitFunctionBody(clang::CodeGen::FunctionArgList&,
clang::Stmt const*) (/usr/local/clang-trunk/bin/clang-4.0+0x1fb6422)
#12 0x0000000001fc12e6
clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl,
llvm::Function*, clang::CodeGen::CGFunctionInfo const&)
(/usr/local/clang-trunk/bin/clang-4.0+0x1fc12e6)
#13 0x0000000001fe0c46
clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl,
llvm::GlobalValue*) (/usr/local/clang-trunk/bin/clang-4.0+0x1fe0c46)
#14 0x0000000001ff14f1
clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl,
llvm::GlobalValue*) (/usr/local/clang-trunk/bin/clang-4.0+0x1ff14f1)
#15 0x0000000001ff28b0
clang::CodeGen::CodeGenModule::EmitGlobal(clang::GlobalDecl)
(/usr/local/clang-trunk/bin/clang-4.0+0x1ff28b0)
#16 0x0000000001ff303d
clang::CodeGen::CodeGenModule::EmitTopLevelDecl(clang::Decl*) [clone
.part.6429] (/usr/local/clang-trunk/bin/clang-4.0+0x1ff303d)
#17 0x00000000025841ab (anonymous
namespace)::CodeGeneratorImpl::HandleTopLevelDecl(clang::DeclGroupRef)
(/usr/local/clang-trunk/bin/clang-4.0+0x25841ab)
#18 0x000000000257e98c
clang::BackendConsumer::HandleTopLevelDecl(clang::DeclGroupRef)
(/usr/local/clang-trunk/bin/clang-4.0+0x257e98c)
#19 0x00000000028f90f6 clang::ParseAST(clang::Sema&, bool, bool)
(/usr/local/clang-trunk/bin/clang-4.0+0x28f90f6)
#20 0x000000000257f4ae clang::CodeGenAction::ExecuteAction()
(/usr/local/clang-trunk/bin/clang-4.0+0x257f4ae)
#21 0x000000000228398e clang::FrontendAction::Execute()
(/usr/local/clang-trunk/bin/clang-4.0+0x228398e)
#22 0x00000000022590f6
clang::CompilerInstance::ExecuteAction(clang::FrontendAction&)
(/usr/local/clang-trunk/bin/clang-4.0+0x22590f6)
#23 0x0000000002311ed2
clang::ExecuteCompilerInvocation(clang::CompilerInstance*)
(/usr/local/clang-trunk/bin/clang-4.0+0x2311ed2)
#24 0x0000000000b49e00 cc1_main(llvm::ArrayRef<char const*>, char const*,
void*) (/usr/local/clang-trunk/bin/clang-4.0+0xb49e00)
#25 0x0000000000af5e52 main (/usr/local/clang-trunk/bin/clang-4.0+0xaf5e52)
#26 0x00007f8eea0bbec5 __libc_start_main
/build/eglibc-3GlaMS/eglibc-2.19/csu/libc-start.c:321:0
#27 0x0000000000b45dad _start (/usr/local/clang-trunk/bin/clang-4.0+0xb45dad)
Stack dump:
0. Program arguments: /usr/local/clang-trunk/bin/clang-4.0 -cc1 -triple
x86_64-unknown-linux-gnu -emit-obj -mrelax-all -disable-free -main-file-name
small.c -mrelocation-model static -mthread-model posix -mdisable-fp-elim
-fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables
-fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb
-coverage-file /data2/small.c -resource-dir
/usr/local/clang-trunk/bin/../lib/clang/4.0.0 -internal-isystem
/usr/local/include -internal-isystem
/usr/local/clang-trunk/bin/../lib/clang/4.0.0/include -internal-externc-isystem
/usr/include/x86_64-linux-gnu -internal-externc-isystem /include
-internal-externc-isystem /usr/include -fdebug-compilation-dir /data2
-ferror-limit 19 -fmessage-length 175 -fobjc-runtime=gcc
-fdiagnostics-show-option -fcolor-diagnostics -o small.o -x c small.c
1. <eof> parser at end of file
2. small.c:1:6: LLVM IR generation of declaration 'foo'
3. small.c:1:6: Generating code for declaration 'foo'
clang-4.0: error: unable to execute command: Aborted (core dumped)
clang-4.0: error: clang frontend command failed due to signal (use -v to see
invocation)
clang version 4.0.0 (trunk 279116)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/local/clang-trunk/bin
clang-4.0: note: diagnostic msg: PLEASE submit a bug report to
<a href="http://llvm.org/bugs/">http://llvm.org/bugs/</a> and include the crash backtrace, preprocessed source, and
associated run script.
clang-4.0: note: diagnostic msg:
********************
PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang-4.0: note: diagnostic msg: /tmp/small-d3bc85.c
clang-4.0: note: diagnostic msg: /tmp/small-d3bc85.sh
clang-4.0: note: diagnostic msg:
********************
$
----------------------------------------------------
void foo ()
{
double a;
// should be: __asm__ ("": "=t" (a):"0" (0.0));
__asm__ ("": "=t" (a):"0" (0));
}</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>