LTO build failure on Windows (for ESP32-S3, LovyanGFX) CreateProcess: No such file or directory

[Szetya]

Description:
When building the Meshtastic project on Windows (10 64-bit) with PlatformIO, using ESP32-S3 environments (including LovyanGFX variants), the build fails with the following error:

lto-wrapper.exe: fatal error: CreateProcess: No such file or directory
ld returned 1 exit status
*** [.pio\build\<env>\firmware.elf] Error 1

Environment:

OS: Windows 10 64-bit

PlatformIO Core: 6.1.19a2

Toolchain: xtensa-esp32s3-elf@8.4.0+2021r2-patch5

Project path: deep folder structure (e.g., /variants/MCU/DEVICE/...)

VSCode + PlatformIO extension

What I tried:

Moving .platformio to a shorter path (d:\pio)

Deleting the project .pio build folder

Fresh clone of the repository

Comparing local build with GitHub Actions build (all toolchains and frameworks matched)

What solved the issue:
Adding the following to platformio.ini successfully allowed the build to complete:

build_unflags = -flto
build_flags = -fno-lto

Notes:

The project builds fine on GitHub Actions, so this appears to be a Windows-specific LTO/path issue.

It may be helpful to document or include platform-specific build flags for Windows S3 environments to prevent similar issues for other contributors.

[mverch67]

What solved the issue:

It doesn't actually solve the issue as the firmware.bin gets ~300 kB larger. It's just a workaround for the limitations of the restricted linker command line (< 32 kB) on the Windows platform.

[Szetya]

I didn't know that.
However, I have been struggling with this problem for a very long time and it seems that I have finally found a solution.
Do you have any other useful advice? Or is Linux the only solution?

[mverch67]

Do you have any other useful advice? Or is Linux the only solution?

On Windows you can use WSL2 and the vscode Remote Development plugin which gives you a smooth transparent link to the Linux world with all benefits including source level debugging for native.

[Szetya]

Thank you! I will definitely try it out in the next few days. 😇

[Szetya]

Thanks for your help! Everything is working fine.