Build failure due to uninitialised variables

[liamjm36]

Hey, I've been trying to run esp_rlottie on an ESP32-P4 evaluation board and I am encountering the following build errror.

idf/esp_rlottie/rlottie/CMakeFiles/rlottie.dir/src/vector/varenaalloc.cpp.obj -MF esp-idf/esp_rlottie/rlottie/CMakeFiles/rlottie.dir/src/vector/varenaalloc.cpp.obj.d -o esp-idf/esp_rlottie/rlottie/CMakeFiles/rlottie.dir/src/vector/varenaalloc.cpp.obj -c ../components/esp_rlottie/rlottie/src/vector/varenaalloc.cpp
../components/esp_rlottie/rlottie/src/vector/varenaalloc.cpp: In member function 'void VArenaAlloc::reset()':
../components/esp_rlottie/rlottie/src/vector/varenaalloc.cpp:42:28: error: '*this.VArenaAlloc::fFirstBlock' is used uninitialized [-Werror=uninitialized]
   42 |     new (this) VArenaAlloc{fFirstBlock, fFirstSize, fFirstHeapAllocationSize};
      |                            ^~~~~~~~~~~
../components/esp_rlottie/rlottie/src/vector/varenaalloc.cpp:42:41: error: '*this.VArenaAlloc::fFirstSize' is used uninitialized [-Werror=uninitialized]
   42 |     new (this) VArenaAlloc{fFirstBlock, fFirstSize, fFirstHeapAllocationSize};
      |                                         ^~~~~~~~~~
../components/esp_rlottie/rlottie/src/vector/varenaalloc.cpp:42:53: error: '*this.VArenaAlloc::fFirstHeapAllocationSize' is used uninitialized [-Werror=uninitialized]
   42 |     new (this) VArenaAlloc{fFirstBlock, fFirstSize, fFirstHeapAllocationSize};
      |                                                     ^~~~~~~~~~~~~~~~~~~~~~~~
At global scope:

Im using ESP-IDF v5.4-dev and LVGL 8.3.11. Do you have any idea why I might be seeing this, or idea on how to resolve the issue?

[0015]

@liamjm36 I haven't tested it on the ESP32-P4 board yet. I'll come back once I figure out what's causing the issue.

[rajivkaggarwal]

I worked around this by adding a gcc pragma to not check if uninitialized:

In rlottie/src/vector/varenaalloc.cpp:

void VArenaAlloc::reset() {
    this->~VArenaAlloc();

#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wuninitialized"
    new (this) VArenaAlloc{fFirstBlock, fFirstSize, fFirstHeapAllocationSize};
#pragma GCC diagnostic pop

}

Not sure if this is the best idea. But it looks like those variables are initialized in the call to VArenaAlloc so it shouldn't be a problem...

[0015]

@rajivkaggarwal Thanks for the info. It looks like rLottie is officially available in LVGL 9.2.2, have you tried it?

[rajivkaggarwal]

I thought rLottie was deprecated in LVGL 9.x. So I'm using LVGL 8.x.