Using build_opt.h with IDE 2.0 Beta 5 fails verification

[Daedelos]

Attempting to Verify using IDE 2.0 Beta 5 with build_opt.h in sketch folder results in:

arm-none-eabi-g++: error: #line: No such file or directory
arm-none-eabi-g++: error: 1: No such file or directory
Compilation error: Error: 2 UNKNOWN: exit status 1

IDE 1.18.3 with the same sketch & build_opt.h verifies without error

To Reproduce
Install IDE 2.0 Beta 5
place a build_opt.h file containing the line -DHAL_CRC_MODULE_ENABLED
attempt to verify

Expected behavior
Verification as in IDE 1.18.3

Desktop (please complete the following information):

• Windows 10 x64 Pro
• Arduino IDE version 2.0 Beta 5
• STM32 core version: 2.0.0
• Upload method: n/a

Board (please complete the following information):
Generic STM32F1 series

[fpistm]

Hi @Daedelos
Yes I confirm there is an issue.
But this is not related to the core but to the Arduino IDE Beta which does not properly managed .h file.
It seems it try to convert the .h file like an ino file.

#line 1 "c:\\Users\\<username>\\AppData\\Local\\Temp\\.arduinoIDE-unsaved2021410-37444-aykylf.uyhtw\\sketch_may10a\\build_opt.h"
-DHAL_CRC_MODULE_ENABLED

I've opened an issue to the Arduino IDE GitHub repo: arduino/arduino-ide#363