On Wed, 2023-11-08 at 17:20 +0800, WANG Rui wrote: > > then the linked binary triggers a SIGBUS. Ideally this should be > > detected by the linker at link time, but currently the BFD linker > > fails > > to detect this error (FWIW this flaw is caused by a really nasty > > method > > for the medium code model implementation). So to me -fno-direct- > > access- > > external-data is the default. I also grepped for -fdirect-access- > > external-data in the kernel building system but I've not found any > > match. > > > > Are you using a different version of Clang, or maybe Clang has some > > configuration-time option to make -fdirect-access-external-data the > > default? > > The clang enables `direct-access-external-data` by default in PIC and > disables it by default in no-PIC. This also applies to PIE. [1] Oh sh*t: xry111@nanmen2 ~ $ clang t1.c -O2 -fno-pie -no-pie xry111@nanmen2 ~ $ ./a.out Bus error (core dumped) I'll consider it a Clang bug then. -- Xi Ruoyao <xry111@xxxxxxxxxxx> School of Aerospace Science and Technology, Xidian University
