If an output section does not have internal . = ALIGN(x);, the spacing among
its input sections remain unchanged after script->assignAddresses is called
for the first time.
r_offset is inputSec->getOutputSection().addr + inputSec->outSecOff + offsetInSec
If we delay inputSec->getOutputSection().addr addition to writeTo,
updateAllocSize can be called only once.
Conservatively use !hasSectionsCommand to mean .relr.dyn only needs one update.
With this change, the problem described by D67164 is very difficult to trigger.
I cannot figure out a case to get the ".relr.dyn needs ... padding word(s)"
diagnostic, but keep it just in case.
My --threads=8 chrome link is 1% faster.