If you have bumped into this locked thread:
https://github.com/esphome/issues/issues/3904
You may be facing NEITHER a PlatformIO bug NOR an ESPHome bug. IF you are on a non-64-bit Raspberry Pi 2 (so, most of them, I think, but some were 64-bit-capable), it might just be that the toolchain was linked incorrectly for Ubuntu (and probably all Debian-based distros). The easy way to tell is:
$ uname -a
Linux pi 5.15.0-1071-raspi #74-Ubuntu SMP PREEMPT Fri Jan 17 12:09:29 UTC 2025 armv7l armv7l armv7l GNU/Linux
If you see 'aarch64' or you aren't on Ubuntu 22.04, then the thread is 100% a better source of info than this post.
Of interest is the first error in this post:
https://github.com/esphome/issues/issues/3904#issuecomment-1552547642
$ ./.esphome/platformio/packages/toolchain-xtensa-esp32/bin/xtensa-esp32-elf-g++
-bash: ./.esphome/platformio/packages/toolchain-xtensa-esp32/bin/xtensa-esp32-elf-g++: No such file or directory
We can elaborate with strace:
$ strace ./xtensa-esp32s3-elf-g++
execve("./xtensa-esp32s3-elf-g++", ["./xtensa-esp32s3-elf-g++"], 0xbedd91a0 /* 27 vars */) = -1 ENOENT (No such file or directory)
strace: exec: No such file or directory
+++ exited with 1 +++
See, this means that the ENOENT comes from very, very early in process start. In my experience (please don't ask), this means the loader is missing, which, indeed, it is:
$ file xtensa-esp32s3-elf-g++
xtensa-esp32s3-elf-g++: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.3, for GNU/Linux 3.2.0, BuildID[sha1]=3b97cade4ee2d3b55df21b3dd333eb95dd42f5dd, stripped
$ file /lib/ld-linux.so.3
/lib/ld-linux.so.3: cannot open `/lib/ld-linux.so.3' (No such file or directory)
I was worried that the EABI5 and armv7l mismatch was going to cause problems, but no, as mentioned here:
https://github.com/esphome/issues/issues/3904#issuecomment-1554071496
it's just a matter of letting the kernel find the dynamic loader where the ELF binary says it should be:
$ sudo ln -s /lib/arm-linux-gnueabihf/ld-linux.so.3 /lib/ld-linux.so.3
In my case that was actually:
$ sudo ln -s /lib/arm-linux-gnueabihf/ld-linux.so.3 /lib/ld-linux.so.3
So, maybe it could be considered a PlatformIO bug that it pulls an Espressif toolchain with bad dynamic linking configuration, an Espressif toolchain bug that their toolchain was not available linked for Ubuntu, or a Linux bug that dynamically linked binaries are a kludge. Either way, acidic and vague as they are on that thread, [ssieb] is right that this is NOT an ESPHome bug.
