[LLD] getMipsN32RelType parameter type mismatch after scanOne interface change

[autostudiolea]

@MaskRay

After commit [66c08d9], the scanOne function signature was changed from:

template <class ELFT, class RelTy> void scanOne(RelTy *&i);

to:

template <class ELFT, class RelTy> void scanOne(typename Relocs<RelTy>::const_iterator &i);

However, the getMipsN32RelType function was not updated accordingly, causing a compilation error when !(ELFT::Is64Bits || RelTy::IsCrel) and ctx.arg.mipsN32Abi is true.

In RelocationScanner::scanOne, when the condition constexpr (ELFT::Is64Bits || RelTy::IsCrel) is false and ctx.arg.mipsN32Abi is true, the code calls:

type = getMipsN32RelType(i);

But getMipsN32RelType still expects the old parameter type:

template <class RelTy> RelType getMipsN32RelType(RelTy *&rel) const;

This causes a type mismatch error because i is now of type typename Relocs<RelTy>::const_iterator & instead of RelTy *&.

[llvmbot]

@llvm/issue-subscribers-lld-elf

Author: None (autostudiolea)

@MaskRay

After commit [66c08d9], the scanOne function signature was changed from:

template <class ELFT, class RelTy> void scanOne(RelTy *&i);

to:

template <class ELFT, class RelTy> void scanOne(typename Relocs<RelTy>::const_iterator &i);

However, the getMipsN32RelType function was not updated accordingly, causing a compilation error when !(ELFT::Is64Bits || RelTy::IsCrel) and ctx.arg.mipsN32Abi is true.

In RelocationScanner::scanOne, when the condition constexpr (ELFT::Is64Bits || RelTy::IsCrel) is false and ctx.arg.mipsN32Abi is true, the code calls:

type = getMipsN32RelType(i);

But getMipsN32RelType still expects the old parameter type:

template <class RelTy> RelType getMipsN32RelType(RelTy *&rel) const;

This causes a type mismatch error because i is now of type typename Relocs<RelTy>::const_iterator & instead of RelTy *&.

[MaskRay]

I am confused. Is this build issue only reproducible on a mips N32 host? Do you have patch to fix it?

[autostudiolea]

I am confused. Is this build issue only reproducible on a mips N32 host? Do you have patch to fix it?

In fact, it will cause a build-time error whenever the condition (ELFT::Is64Bits || RelTy::IsCrel) evaluates to false. Unfortunately, I don't have a patch available right now.