[5.5] Revert "[VFS] Fix inconsistencies between relative paths and fallthrough in the RedirectingFileSystem"

[keith]

This fixes https://bugs.swift.org/browse/SR-15123 where #fileID and
friends, and error messages, when using a vfsoverlay would always be
absolute paths even when the file paths to the invocation were relative.

This likely isn't the right long term fix, but is likely the safest fix
for now.

This reverts 0be9ca7

[keith]

@fredriss since you're mentioned as the release manager

[keith]

@JDevlieghere since you were the original author here

[keith]

Hoping we can get a longer fix here for reference: https://reviews.llvm.org/D109128

[JDevlieghere]

Talked this over with Keith offline. I believe reverting my patch is the right thing to do at this point in the release.

[JDevlieghere]

@swift-ci please test

[keith]

The test failure here does not appear to be related

[JDevlieghere]

@swift-ci please test macos platform

[JDevlieghere]

@swift-ci please test macos platform

[keith]

FAIL: Swift(macosx-x86_64) :: Frontend/emit-module-path-wmo.swift (1231 of 14692)
******************** TEST 'Swift(macosx-x86_64) :: Frontend/emit-module-path-wmo.swift' FAILED ********************
Script:
--
: 'RUN: at line 1';   rm -rf "/Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp" && mkdir -p "/Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp"
: 'RUN: at line 3';   cd /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp; /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/bin/swift-frontend -target x86_64-apple-macosx10.9  -module-cache-path /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/swift-test-results/x86_64-apple-macosx10.9/clang-module-cache -sdk '/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.0.sdk'  -swift-version 4  -define-availability 'SwiftStdlib 5.5:macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0' -typo-correction-limit 10  -emit-module -module-name foo -whole-module-optimization /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/swift/test/Frontend/emit-module-path-wmo.swift
: 'RUN: at line 4';   test -f /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp/foo.swiftmodule
: 'RUN: at line 6';   rm -rf "/Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp" && mkdir -p "/Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp"
: 'RUN: at line 7';   /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/bin/swift-frontend -target x86_64-apple-macosx10.9  -module-cache-path /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/swift-test-results/x86_64-apple-macosx10.9/clang-module-cache -sdk '/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.0.sdk'  -swift-version 4  -define-availability 'SwiftStdlib 5.5:macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0' -typo-correction-limit 10  -emit-module -module-name foo -emit-module-path /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp/bar.swiftmodule -whole-module-optimization /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/swift/test/Frontend/emit-module-path-wmo.swift
: 'RUN: at line 8';   test -f /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp/bar.swiftmodule
: 'RUN: at line 9';   not test -f /Users/buildnode/jenkins/workspace/apple-llvm-project-pr-macos/buildbot_incremental/swift-macosx-x86_64/test-macosx-x86_64/Frontend/Output/emit-module-path-wmo.swift.tmp/foo.swiftmodule
--
Exit Code: 1

Command Output (stderr):
--
<unknown>:0: warning: no such sysroot directory: '/Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.0.sdk'
<unknown>:0: error: missing required module 'SwiftShims'

--

This appears to be the failure

[JDevlieghere]

@swift-ci please test

[keith]

same failure. it looks like the most recent commits on this branch didn't come through PRs at all, is there a way to see if it's red without this (aside from submitting a new empty PR and testing there)

[shepting]

This is impacting us as well (currently blocking our upgrade to Xcode 13 and Monterey).

[keith]

This definitely missed the train, this fix is included in 5.6 which shipped with Xcode 13.3