Comment 1 for bug 2038340

Can confirm this.

OS: Ubuntu 22.04 LTS

Clang version:
```
Ubuntu clang version 14.0.0-1ubuntu1.1
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
```

C++ code example:

```c++
#include <iostream>

using std::cout;
using std::endl;

int main(int argc, char** argv) {
    cout << "Hello, world!" << endl;
    return 0;
}
```

Tried `clang++ -v main.cc`, and got this:

```
Ubuntu clang version 14.0.0-1ubuntu1.1
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/11
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12
Selected GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12
Candidate multilib: .;@m64
Selected multilib: .;@m64
 "/usr/lib/llvm-14/bin/clang" -cc1 -triple x86_64-pc-linux-gnu -emit-obj -mrelax-all --mrelax-relocations -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name main-kmp.cc -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -mllvm -treat-scalable-fixed-error-as-warning -debugger-tuning=gdb -v -fcoverage-compilation-dir=/home/tianxing/dev/algorithms/KMP -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++ -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/x86_64-linux-gnu -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fdeprecated-macro -fdebug-compilation-dir=/home/tianxing/dev/algorithms/KMP -ferror-limit 19 -fgnuc-version=4.2.1 -fcxx-exceptions -fexceptions -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/main-kmp-a7fd49.o -x c++ main-kmp.cc
clang -cc1 version 14.0.0 based upon LLVM 14.0.0 default target x86_64-pc-linux-gnu
ignoring nonexistent directory "/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/backward"
ignoring nonexistent directory "/usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../x86_64-linux-gnu/include"
ignoring nonexistent directory "/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++
 /usr/lib/llvm-14/lib/clang/14.0.0/include
 /usr/local/include
 /usr/include/x86_64-linux-gnu
 /usr/include
End of search list.
main.cc:1:10: fatal error: 'iostream' file not found
#include <iostream>
         ^~~~~~~~~~
1 error generated.
```

Looks like it explicitly wants libstdc++-12-dev header & library files.