Fix portable PDB debug reservation after path mapping - #20509
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| yield "--target:library" | ||
| yield "--deterministic+" | ||
| yield $"--debug:{debugType}" | ||
| yield $"--pathmap:{workDir}={mappedRoot}" |
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🤖 🕵️ All three cases fail with FS2028 when TEMP contains spaces because runFscProcess joins unquoted arguments.
$env:TEMP = Join-Path ([IO.Path]::GetTempPath()) 'with spaces'
$env:TMP = $env:TEMP
New-Item -ItemType Directory -Force $env:TEMP | Out-Null
dotnet test --project tests\FSharp.Compiler.ComponentTests\FSharp.Compiler.ComponentTests.fsproj -c Debug --no-build -p:BUILDING_USING_DOTNET=true -p:FSHARPCORE_USE_PACKAGE=false -- --filter-method '*Path mapping removes original PDB path length from the entire binary*'
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runToolProcess (behind runFscProcess / runFsiProcess) built the child command line with String.concat " ", so any argument containing a space was split into several arguments by the child's command-line parser. This surfaced on the .NET Framework test legs, where the default references passed via CompilerAssert.DefaultProjectOptions live under "C:\Program Files (x86)\Reference Assemblies\...". fsc saw "C:\Program" and "Files" as separate tokens and failed with error FS2020: The assembly 'Assemblies\Microsoft\Framework\ .NETFramework\v4.7.2\Microsoft.CSharp.dll' is listed on the command line. Assemblies should be referenced using a command line flag such as '-r'. The same splitting applies to any test whose paths come from a temp directory containing spaces. Quote arguments that contain whitespace. Arguments without whitespace are passed through unchanged, so existing callers are unaffected. The determinism test now builds under a temp root containing a space so the behaviour stays covered.
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Description
--pathmapdoesn't make portable-PDB output path-independent. Compiling identical source from twodirectories whose paths differ in length, with
--deterministic+and both mapped to the same root,produces different DLLs. Measured on a real repo: PDBs byte-identical, 55 DLL bytes differ.
Cause: in
writeBinaryAux(ilwrite.fs) the debug-directory chunk is reserved from the originalpdb path (
Unicode.GetByteCount f + 40slack), but the bytes written are the mapped path. Thereservation — and the 4-byte-aligned layout after it — tracks a path that never appears in the output.
Fix: for portable PDBs reserve exactly what CodeView writes — 24-byte header + mapped path as UTF-8
bug 748444slack) isdeliberately unchanged; embedded PDBs reserve from the file name.
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