From: Matthias Kaehlcke > Sent: 17 September 2018 22:33 > > sysrq_handle_crash() dereferences a NULL pointer on purpose to force > an exception, the local variable 'killer' is assigned to NULL and > dereferenced later. Clang detects the NULL pointer dereference at compile > time and emits a BRK instruction (on arm64) instead of the expected NULL > pointer exception. Change 'killer' to a global variable (and rename it > to 'sysrq_killer' to avoid possible clashes) to prevent Clang from > detecting the condition. By default global variables are initialized > with zero/NULL in C, therefore an explicit initialization is not needed.
You need an explicit initialiser in order to make it global data rather than a common section. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)