Fix portable PDB debug reservation after path mapping - #20509
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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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🔍 Tooling Safety Check — Affects-Compiler-Output, Affects-Test-Tooling
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Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01WSJjjqTJwPxHnT7ihY83ee
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cc @abonie sorry the release note file moved from under me so had to push after your approval |
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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.
Checklist