boards.txt underscore in name causes problems

[NicoHood]

An example:

menu.usbcore=USB Core

leonardoExtended.name=Arduino Leonardo Custom HID
leonardoExtended.vid.0=0x2341
leonardoExtended.pid.0=0x0036
leonardoExtended.vid.1=0x2341
leonardoExtended.pid.1=0x8036
leonardoExtended.upload.tool=arduino:avrdude
leonardoExtended.upload.protocol=avr109
leonardoExtended.upload.maximum_size=28672
leonardoExtended.upload.maximum_data_size=2560
leonardoExtended.upload.speed=57600
leonardoExtended.upload.disable_flushing=true
leonardoExtended.upload.use_1200bps_touch=true
leonardoExtended.upload.wait_for_upload_port=true

leonardoExtended.bootloader.tool=arduino:avrdude
leonardoExtended.bootloader.low_fuses=0xff
leonardoExtended.bootloader.high_fuses=0xd8
leonardoExtended.bootloader.extended_fuses=0xcb
leonardoExtended.bootloader.file=arduino:caterina/Caterina-leonardo.hex
leonardoExtended.bootloader.unlock_bits=0x3F
leonardoExtended.bootloader.lock_bits=0x2F

leonardoExtended.build.mcu=atmega32u4
leonardoExtended.build.f_cpu=16000000L
leonardoExtended.build.vid=0x2341
leonardoExtended.build.pid=0x8036
leonardoExtended.build.usb_product="Arduino Leonardo"
leonardoExtended.build.board=AVR_LEONARDO
leonardoExtended.build.core=arduino:hid
#leonardoExtended.build.variant=arduino:leonardo
leonardoExtended.build.extra_flags={build.usb_flags}


#USB core selection
#HID Project needs to be installed https://github.com/NicoHood/HID
#TODO change to HID:hid
leonardoExtended.menu.usbcore.hid=Serial + Extended HID
leonardoExtended.menu.usbcore.hid.build.variant=leonardo_hid
leonardoExtended.menu.usbcore.gamepad=Serial + Gamepad HID
leonardoExtended.menu.usbcore.gamepad.build.variant=leonardo_gamepad
leonardoExtended.menu.usbcore.custom=Serial + Custom HID
leonardoExtended.menu.usbcore.custom.build.variant=leonardo_custom
leonardoExtended.menu.usbcore.USB_CORE=Default Core
leonardoExtended.menu.usbcore.USB_CORE.build.variant=arduino:leonardo
leonardoExtended.menu.usbcore.USB-CORE.build.core=arduino:arduino
leonardoExtended.menu.usbcore.NO_USB=No USB functions
leonardoExtended.menu.usbcore.NO_USB.build.variant=leonardo_no_usb
leonardoExtended.menu.usbcore.NO_USB.build.core=arduino:arduino

This wouldnt work with leonardo_extended as name. Then the compiler sais that pins_arduino (the variants folder) is not defined. The problem only occurs when you do something like that, with a sub menu.

Example:
https://github.com/NicoHood/HID/tree/e5d28296d2785ef3f16ac4a8dc27edc63f2e6ef6

[cmaglie]

@NicoHood
may you check if cmaglie@e360f82 fixes this problem?