LLVM 3.9 now emits short form of jump instructions, but it is still using
32 bit addresses for some movl instructions. Fortunately it was caught early:
clang ... boot/i386/pc/boot.S
clang -cc1as: fatal error: error in backend: invalid .org offset '440' (at offset '441')
Add additional check to catch it during configure run and force -no-integrated-as.
Closes: 49200
More details in
https://lists.gnu.org/archive/html/grub-devel/2015-02/msg00099.htmlhttps://llvm.org/bugs/show_bug.cgi?id=22662
We already check that jump over 300 bytes gap is 3 bytes in code16-mode.
Some clang versions generate 3-byte opcode for short jumps which makes
boot.img blow over 512-byte limit. Enforce -no-integrated-as in such cases