Error using “clang hello.cpp -o hello -lstdc++ -ccc-print-phases” in WSL Ubuntu 24.04 LTS

[17789289]

using command ： clang hello.cpp -o hello -lstdc++ is OK， but：

clang hello.cpp -o hello -lstdc++ -ccc-print-phases
+- 0: input, "hello.cpp", c++
+- 1: preprocessor, {0}, c++-cpp-output
+- 2: compiler, {1}, ir
+- 3: backend, {2}, assembler
+- 4: assembler, {3}, object
clang: /home/qiwei/llvm-project/llvm/include/llvm/ADT/SmallVector.h:308: const_reference llvm::SmallVectorTemplateCommon<const char *>::operator const [T = const char *]: Assertion `idx < size()' failed.

[EugeneZelenko]

Could you please provide version information, complete crash stack and reproducer, preferably on https://godbolt.org?

[17789289]

Below is my code,it's very simple:

#include
int main() {
std::cout << "Hello world!" << std::endl;
return 0;
}

the issue was occurred at WSL Ubuntu 24.04 LTS platform with Clang 18.1.8

what I have done so far: just run the same code and command (clang hello.cpp -o hello -lstdc++ -ccc-print-phases) in WSL Ubuntu 22.04 LTS platform with clang14, no issue found in the result. But when I run the same command using clang17 and clang18.1.8, same issue raised：

clang hello.cpp -o hello -lstdc++ -ccc-print-phases
+- 0: input, "hello.cpp", c++
+- 1: preprocessor, {0}, c++-cpp-output
+- 2: compiler, {1}, ir
+- 3: backend, {2}, assembler
+- 4: assembler, {3}, object
clang: /home/qiwei/llvm-project/llvm/include/llvm/ADT/SmallVector.h:308: llvm::SmallVectorTemplateCommon::const_reference llvm::SmallVectorTemplateCommon<const char *>::operator const [T = const char *]: Assertion `idx < size()' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0. Program arguments: clang hello.cpp -o hello -lstdc++ -ccc-print-phases

1.  Compilation construction
   

#0 0x00007f9b565aa277 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/qiwei/llvm-project/install/bin/../lib/libLLVMSupport.so.18.1+0x203277)
#1 0x00007f9b565a7dde llvm::sys::RunSignalHandlers() (/home/qiwei/llvm-project/install/bin/../lib/libLLVMSupport.so.18.1+0x200dde)
#2 0x00007f9b565aa94a SignalHandler(int) Signals.cpp:0:0
#3 0x00007f9b55e86520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
#4 0x00007f9b55eda9fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
#5 0x00007f9b55e86476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
#6 0x00007f9b55e6c7f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
#7 0x00007f9b55e6c71b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
#8 0x00007f9b55e7de96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
#9 0x00007f9b58f4f0e9 llvm::SmallVectorTemplateCommon<char const*, void>::operator[](unsigned long) const /home/qiwei/llvm-project/llvm/include/llvm/ADT/SmallVector.h:0:5
#10 0x00007f9b58f8d021 llvm::opt::Arg::getValue(unsigned int) const /home/qiwei/llvm-project/llvm/include/llvm/Option/Arg.h:126:12
#11 0x00007f9b58f77210 PrintActions1(clang::driver::Compilation const&, clang::driver::Action*, std::map<clang::driver::Action*, unsigned int, std::lessclang::driver::Action*, std::allocator<std::pair<clang::driver::Action* const, unsigned int>>>&, llvm::Twine, int) /home/qiwei/llvm-project/clang/lib/Driver/Driver.cpp:2326:37
#12 0x00007f9b58f77542 PrintActions1(clang::driver::Compilation const&, clang::driver::Action*, std::map<clang::driver::Action*, unsigned int, std::lessclang::driver::Action*, std::allocator<std::pair<clang::driver::Action* const, unsigned int>>>&, llvm::Twine, int) /home/qiwei/llvm-project/clang/lib/Driver/Driver.cpp:2359:25
#13 0x00007f9b58f71ba6 clang::driver::Driver::PrintActions(clang::driver::Compilation const&) const /home/qiwei/llvm-project/clang/lib/Driver/Driver.cpp:2398:18
#14 0x00007f9b58f6d4eb clang::driver::Driver::BuildCompilation(llvm::ArrayRef<char const*>) /home/qiwei/llvm-project/clang/lib/Driver/Driver.cpp:1518:12
#15 0x000055839f2dfaf1 clang_main(int, char**, llvm::ToolContext const&) /home/qiwei/llvm-project/clang/tools/driver/driver.cpp:510:44
#16 0x000055839f316bd5 main /home/qiwei/llvm-project/build/tools/clang/tools/driver/clang-driver.cpp:17:3
#17 0x00007f9b55e6dd90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#18 0x00007f9b55e6de40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#19 0x000055839f2debb5 _start (/home/qiwei/llvm-project/install/bin/clang-18+0x42bb5)
Aborted

[llvmbot]

@llvm/issue-subscribers-clang-driver

Author: Dynpro (17789289)

using command ： clang hello.cpp -o hello -lstdc++ is OK， but：

clang hello.cpp -o hello -lstdc++ -ccc-print-phases
+- 0: input, "hello.cpp", c++
+- 1: preprocessor, {0}, c++-cpp-output
+- 2: compiler, {1}, ir
+- 3: backend, {2}, assembler
+- 4: assembler, {3}, object
clang: /home/qiwei/llvm-project/llvm/include/llvm/ADT/SmallVector.h:308: const_reference llvm::SmallVectorTemplateCommon<const char *>::operator const [T = const char *]: Assertion `idx < size()' failed.

[hjyamauchi]

I also hit this issue on a self-built Clang 20.1.x

$ clang -v
Ubuntu clang version 20.1.5 (++20250430014744+ebfae55af454-1~exp1~20250430014805.108)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm-20/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/11
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/12
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/9
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/12
Candidate multilib: .;@m64
Selected multilib: .;@m64
$ clang hello.cpp -lstdc++ -ccc-print-phases
            +- 0: input, "hello.cpp", c++
         +- 1: preprocessor, {0}, c++-cpp-output
      +- 2: compiler, {1}, ir
   +- 3: backend, {2}, assembler
+- 4: assembler, {3}, object
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: clang hello.cpp -lstdc++ -ccc-print-phases
1.	Compilation construction
 #0 0x000070da62e18056 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/lib/llvm-20/bin/../lib/libLLVM.so.20.1+0x1018056)
 #1 0x000070da62e15c50 llvm::sys::RunSignalHandlers() (/usr/lib/llvm-20/bin/../lib/libLLVM.so.20.1+0x1015c50)
 #2 0x000070da62e1870b (/usr/lib/llvm-20/bin/../lib/libLLVM.so.20.1+0x101870b)
 #3 0x000070da61642520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x000070da6179d7fd ./string/../sysdeps/x86_64/multiarch/strlen-avx2.S:74:0
 #5 0x000070da6d082e18 (/usr/lib/llvm-20/bin/../lib/libclang-cpp.so.20.1+0x2882e18)
 #6 0x000070da6d083120 (/usr/lib/llvm-20/bin/../lib/libclang-cpp.so.20.1+0x2883120)
 #7 0x000070da6d075b01 clang::driver::Driver::BuildCompilation(llvm::ArrayRef<char const*>) (/usr/lib/llvm-20/bin/../lib/libclang-cpp.so.20.1+0x2875b01)
 #8 0x0000644caaa106ff clang_main(int, char**, llvm::ToolContext const&) (/usr/lib/llvm-20/bin/clang+0xe6ff)
 #9 0x0000644caaa1d716 main (/usr/lib/llvm-20/bin/clang+0x1b716)
#10 0x000070da61629d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16
#11 0x000070da61629e40 call_init ./csu/../csu/libc-start.c:128:20
#12 0x000070da61629e40 __libc_start_main ./csu/../csu/libc-start.c:379:5
#13 0x0000644caaa0ed75 _start (/usr/lib/llvm-20/bin/clang+0xcd75)
Segmentation fault (core dumped)

Driver.cpp

static unsigned PrintActions1(const Compilation &C, Action *A,
                              std::map<Action *, unsigned> &Ids,
                              Twine Indent = {}, int Kind = TopLevelAction) {
  ...
  os << Action::getClassName(A->getKind()) << ", ";
  if (InputAction *IA = dyn_cast<InputAction>(A)) {
    os << "\"" << IA->getInputArg().getValue() << "\"";                   <----------------- Crashing here
  } else if (BindArchAction *BIA = dyn_cast<BindArchAction>(A)) {
  ...

The debugger shows the following

(lldb) r
Process 3010263 launched: '/home/hiroshi/clang-tools/llvm-project/install/bin/clang' (x86_64)
            +- 0: input, "hello.cpp", c++
         +- 1: preprocessor, {0}, c++-cpp-output
      +- 2: compiler, {1}, ir
   +- 3: backend, {2}, assembler
+- 4: assembler, {3}, object
clang: /home/hiroshi/clang-tools/llvm-project/llvm/include/llvm/ADT/SmallVector.h:308: const T& llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::operator[](llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::size_type) const [with T = const char*; <template-parameter-1-2> = void; llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::const_reference = const char* const&; llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::size_type = long unsigned int]: Assertion `idx < size()' failed.
Process 3010263 stopped
* thread #1, name = 'clang', stop reason = signal SIGABRT
    frame #0: 0x00007fffec6969fc libc.so.6`__GI___pthread_kill [inlined] __pthread_kill_implementation(no_tid=0, signo=6, threadid=140737287673728) at pthread_kill.c:44:76
(lldb) bt
error: libc.so.6 0x0003da11: adding range [0x000000000002870c-0x0000000000028716) which has a base that is less than the function's low PC 0x0000000000039cf0. Please file a bug and attach the file at the start of this error message
* thread #1, name = 'clang', stop reason = signal SIGABRT
  * frame #0: 0x00007fffec6969fc libc.so.6`__GI___pthread_kill [inlined] __pthread_kill_implementation(no_tid=0, signo=6, threadid=140737287673728) at pthread_kill.c:44:76
    frame #1: 0x00007fffec6969b0 libc.so.6`__GI___pthread_kill [inlined] __pthread_kill_internal(signo=6, threadid=140737287673728) at pthread_kill.c:78:10
    frame #2: 0x00007fffec6969b0 libc.so.6`__GI___pthread_kill(threadid=140737287673728, signo=6) at pthread_kill.c:89:10
    frame #3: 0x00007fffec642476 libc.so.6`__GI_raise(sig=6) at raise.c:26:13
    frame #4: 0x00007fffec6287f3 libc.so.6`__GI_abort at abort.c:79:7
    frame #5: 0x00007fffec62871b libc.so.6`__assert_fail_base(fmt="%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion="idx < size()", file="/home/hiroshi/clang-tools/llvm-project/llvm/include/llvm/ADT/SmallVector.h", line=308, function="const T& llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::operator[](llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::size_type) const [with T = const char*; <template-parameter-1-2> = void; llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::const_reference = const char* const&; llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::size_type = long unsigned int]") at assert.c:94:3
    frame #6: 0x00007fffec639e96 libc.so.6`__GI___assert_fail(assertion="idx < size()", file="/home/hiroshi/clang-tools/llvm-project/llvm/include/llvm/ADT/SmallVector.h", line=308, function="const T& llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::operator[](llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::size_type) const [with T = const char*; <template-parameter-1-2> = void; llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::const_reference = const char* const&; llvm::SmallVectorTemplateCommon<T, <template-parameter-1-2> >::size_type = long unsigned int]") at assert.c:103:3
    frame #7: 0x00007ffff209c2ea libclangDriver.so.18.1`llvm::SmallVectorTemplateCommon<char const*, void>::operator[](this=0x0000555555635d30, idx=0) const at SmallVector.h:308:5
    frame #8: 0x00007ffff20db19b libclangDriver.so.18.1`llvm::opt::Arg::getValue(this=0x0000555555635d00, N=0) const at Arg.h:126:20
    frame #9: 0x00007ffff20bdbc1 libclangDriver.so.18.1`PrintActions1(C=0x000055555563a030, A=0x000055555563a7d0, Ids=size=5, Indent=Twine @ 0x00007fffffffc3d0, Kind=2) at Driver.cpp:2326:46
    frame #10: 0x00007ffff20bde95 libclangDriver.so.18.1`PrintActions1(C=0x000055555563a030, A=0x000055555563a8e0, Ids=size=5, Indent=Twine @ 0x00007fffffffc640, Kind=0) at Driver.cpp:2359:79
    frame #11: 0x00007ffff20be26a libclangDriver.so.18.1`clang::driver::Driver::PrintActions(this=0x00007fffffffcfc0, C=0x000055555563a030) const at Driver.cpp:2399:18
    frame #12: 0x00007ffff20b8932 libclangDriver.so.18.1`clang::driver::Driver::BuildCompilation(this=0x00007fffffffcfc0, ArgList=ArrayRef<char const*> @ 0x00007fffffffc720) at Driver.cpp:1517:17
    frame #13: 0x0000555555564d0b clang`clang_main(Argc=6, Argv=0x00007fffffffe3d8, ToolContext=0x00007fffffffe1f0) at driver.cpp:510:66
    frame #14: 0x000055555559feb4 clang`main(argc=6, argv=0x00007fffffffe3d8) at clang-driver.cpp:17:20
    frame #15: 0x00007fffec629d90 libc.so.6`__libc_start_call_main(main=(clang`main at clang-driver.cpp:15:33), argc=6, argv=0x00007fffffffe3d8) at libc_start_call_main.h:58:16
    frame #16: 0x00007fffec629e40 libc.so.6`__libc_start_main_impl(main=(clang`main at clang-driver.cpp:15:33), argc=6, argv=0x00007fffffffe3d8, init=<unavailable>, fini=<unavailable>, rtld_fini=<unavailable>, stack_end=0x00007fffffffe3c8) at libc-start.c:392:3
    frame #17: 0x0000555555562185 clang`_start + 37
(lldb) f 8
frame #8: 0x00007ffff20db19b libclangDriver.so.18.1`llvm::opt::Arg::getValue(this=0x0000555555635d00, N=0) const at Arg.h:126:20
   123 	  unsigned getNumValues() const { return Values.size(); }
   124 	
   125 	  const char *getValue(unsigned N = 0) const {
-> 126 	    return Values[N];
   127 	  }
   128 	
   129 	  SmallVectorImpl<const char *> &getValues() { return Values; }
(lldb) print Values
(llvm::SmallVector<const char *, 2>) {
  llvm::SmallVectorImpl<const char *> = {
    llvm::SmallVectorTemplateBase<const char *> = {
      llvm::SmallVectorTemplateCommon<const char *> = {
        llvm::SmallVectorBase<unsigned int> = (BeginX = 0x0000555555635d40, Size = 0, Capacity = 2)
      }
    }
  }
  llvm::SmallVectorStorage<const char *, 2> = (InlineElts = "M\x80`UUU\0\0V\x80`UUU")
}

It looks like it's crashing because the input arg has zero values when it seems expected to have at least one value.

As clang++ hello.cpp -ccc-print-phases doesn't crash, it may be related to the -lstdc++ being internally added when the driver is invoked for a cpp file as clang, as opposed to clang++.