clang: PDB generated from cross-compiled mingw targets don't have source lines for MS debuggers

[nedsociety]

• Ubuntu clang version 15.0.2-++20220926063022+451e3b68306d-1~exp1~20220926063118.66
• mingw-w64 9.4
• Build configuration:
  • Target triplet: i686-w64-windows-gnu target
  • The binary was cross-compiled from Ubuntu, so no clang-cl nor lld-link but instead clang and ld.lld are used.
  • Compiler call includes -g -gcodeview
  • Linker call to the driver includes -fuse-ld=lld-15 -debug -Xlinker -pdb=Hyperspace.pdb

The generated PDB, when plugged into VS2022 debugging session, shows the following message when the debugger is stopped:

Note that the symbol names are somewhat available from the Call Stacks window below (Hyperspace.dll!__do_global_ctors()). The name isn't shown when the PDB is not present, so I guess PDB does provide symbol names but not source lines for some reason.

Expected behavior is that VS IDE should ask where the source file is.

[llvmbot]

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