547255 - Make DWARF addresses load-address-relative

Status: RESOLVED FIXED

(Servo Graveyard :: Rust, defect)

Description

[Graydon Hoare :graydon]

Address attributes in DIEs are taken as relative to a shared-relocatable unit's base address (see DWARF standard section 7.3), whereas currently we are emitting them as absolute and "correcting" for relocation on the fly by subtracting out the crate relocation distance. This works for us but won't for other DWARF consumers. Need to do the right thing, which means crates should learn their load address. Place an "image base" fixup in the semant ctxt, emit it as a MARK in the 0th position of the first load-segment, and store distance-to-that in the crate as well; then add that distance at runtime to the crate-relocation distance.

Comment 1

[Graydon Hoare :graydon]

Fixed in 3294f694b5d2.