bug#42819: problem running xtensa-esp32-elf-g++

[Wensheng Xie]

Dear guix:

I have installed https://github.com/sudomesh/disaster-radio under guix 1.1.0

```
wxie@guix ~/work/disaster-radio/firmware$ pip install -U platformio
Defaulting to user installation because normal site-packages is not writeable
Requirement already up-to-date: platformio in 
/home/wxie/.local/lib/python3.8/site-packages (4.3.4)
Requirement already satisfied, skipping upgrade: bottle<0.13 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (0.12.18)
Requirement already satisfied, skipping upgrade: click<8,>=5 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (7.1.2)
Requirement already satisfied, skipping upgrade: colorama in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (0.4.3)
Requirement already satisfied, skipping upgrade: pyserial!=3.3,<4,>=3 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (3.4)
Requirement already satisfied, skipping upgrade: requests<3,>=2.4.0 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (2.24.0)
Requirement already satisfied, skipping upgrade: semantic_version<3,>=2.8.1 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (2.8.5)
Requirement already satisfied, skipping upgrade: tabulate<1,>=0.8.3 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (0.8.7)
Requirement already satisfied, skipping upgrade: pyelftools<1,>=0.25 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (0.26)
Requirement already satisfied, skipping upgrade: marshmallow>=2 in 
/home/wxie/.local/lib/python3.8/site-packages (from platformio) (3.7.1)
Requirement already satisfied, skipping upgrade: 
urllib3!=1.25.0,!=1.25.1,<1.26,>=1.21.1 in 
/home/wxie/.local/lib/python3.8/site-packages (from 
requests<3,>=2.4.0->platformio) (1.25.10)
Requirement already satisfied, skipping upgrade: chardet<4,>=3.0.2 in 
/home/wxie/.local/lib/python3.8/site-packages (from 
requests<3,>=2.4.0->platformio) (3.0.4)
Requirement already satisfied, skipping upgrade: certifi>=2017.4.17 in 
/home/wxie/.local/lib/python3.8/site-packages (from 
requests<3,>=2.4.0->platformio) (2020.6.20)
Requirement already satisfied, skipping upgrade: idna<3,>=2.5 in 
/home/wxie/.local/lib/python3.8/site-packages (from 
requests<3,>=2.4.0->platformio) (2.10)
```

However, somehow the command is not working
```
Converting main.ino
sh: 
/home/wxie/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-g++: 
Datei oder Verzeichnis nicht gefunden
*** Error 127
```

I checked the file, it exists, but
```
wxie@guix ~/.platformio/packages/toolchain-xtensa32/bin$ ./xtensa-esp32-elf-gcc
bash: ./xtensa-esp32-elf-gcc: Datei oder Verzeichnis nicht gefunden
wxie@guix ~/.platformio/packages/toolchain-xtensa32/bin$ ./xtensa-esp32-elf-g++
bash: ./xtensa-esp32-elf-g++: Datei oder Verzeichnis nicht gefunden
wxie@guix ~/.platformio/packages/toolchain-xtensa32/bin$ ./xtensa-esp32-elf-cpp
bash: ./xtensa-esp32-elf-cpp: Datei oder Verzeichnis nicht gefunden
wxie@guix ~/.platformio/packages/toolchain-xtensa32/bin$ sh 
./xtensa-esp32-elf-cpp
./xtensa-esp32-elf-cpp: ./xtensa-esp32-elf-cpp: Kann die Datei nicht ausführen.
wxie@guix ~/.platformio/packages/toolchain-xtensa32/bin$ sh 
./xtensa-esp32-elf-g++
./xtensa-esp32-elf-g++: ./xtensa-esp32-elf-g++: Kann die Datei nicht ausführen.
```

What could be the problem? Does guix support this?

best regards,
wxie