Trouble running example PNG parser and `swift test`.

[zaneenders]

Hi, I'm having trouble running the example swift run parser-test Data/PNG/tiny.png as well as running swift test.

Installed using swiftly

MacOS 15.5 (24F74)
main commit d4724d1d6f5da8526320f1990df9e2bd59dd2911

➜  swift-binary-parsing git:(main) swift --version
Apple Swift version 6.2-dev (LLVM 3c4a54b02dd62b7, Swift a40a7be6945a895)
Target: arm64-apple-macosx15.0
Build config: +assertions

Checklist

• If possible, I've reproduced the issue using the main branch of this package
• I've searched for existing GitHub issues

Steps to Reproduce

I have cloned the repo and successfully built the project using swift build -c release but when running the example command swift run parser-test Data/PNG/tiny.png I get the error listed above.

➜  swift-binary-parsing git:(main) swift run parser-test Data/PNG/tiny.png
[1/1] Planning build
Building for debugging...
[1/1] Write swift-version-78A6468B061A2804.txt
Build of product 'parser-test' complete! (1.01s)
dyld[4434]: Symbol not found: _$ss7RawSpanVMn
  Referenced from: <78C33C96-E864-33AB-9775-024ABF9B7582> /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/parser-test
  Expected in:     <26919DE5-6960-3FDC-BBDC-4E6C8C8470B1> /usr/lib/swift/libswiftCore.dylib

I also get the following error when running swift test. I'm not sure what "reinstalling the bundle" means though. I have tired reinstalling the toolchain and rebooting my computer.

[#DeprecatedDeclaration]: <https://docs.swift.org/compiler/documentation/diagnostics/deprecated-declaration>
warning: input verification failed
note: while processing /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/BinaryParsingMacros-tool.build/SyntaxVisitorPredicate.swift.o
[209/209] Linking swift-binary-parsingPackageTests
Build complete! (46.23s)
The bundle “swift-binary-parsingPackageTests.xctest” couldn’t be loaded. Try reinstalling the bundle.
(dlopen(/Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests, 0x0109): Symbol not found: _$ss7RawSpanVMn
  Referenced from: <74755BC8-9B1F-3A23-B3E7-93B40E7EAB16> /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests
  Expected in:     <26919DE5-6960-3FDC-BBDC-4E6C8C8470B1> /usr/lib/swift/libswiftCore.dylib)
swiftpm_testing_helper/Entrypoint.swift:34: Fatal error: Failed to open test bundle at path /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests: dlopen(/Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests, 0x0101): Symbol not found: _$ss7RawSpanVMn
  Referenced from: <74755BC8-9B1F-3A23-B3E7-93B40E7EAB16> /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests
  Expected in:     <26919DE5-6960-3FDC-BBDC-4E6C8C8470B1> /usr/lib/swift/libswiftCore.dylib
error: Exited with unexpected signal code 5

Expected behavior

The example should run and test should at least build.

Actual behavior

➜  swift-binary-parsing git:(main) swift run parser-test Data/PNG/tiny.png
[1/1] Planning build
Building for debugging...
[1/1] Write swift-version-78A6468B061A2804.txt
Build of product 'parser-test' complete! (1.01s)
dyld[4434]: Symbol not found: _$ss7RawSpanVMn
  Referenced from: <78C33C96-E864-33AB-9775-024ABF9B7582> /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/parser-test
  Expected in:     <26919DE5-6960-3FDC-BBDC-4E6C8C8470B1> /usr/lib/swift/libswiftCore.dylib

[#DeprecatedDeclaration]: <https://docs.swift.org/compiler/documentation/diagnostics/deprecated-declaration>
warning: input verification failed
note: while processing /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/BinaryParsingMacros-tool.build/SyntaxVisitorPredicate.swift.o
[209/209] Linking swift-binary-parsingPackageTests
Build complete! (46.23s)
The bundle “swift-binary-parsingPackageTests.xctest” couldn’t be loaded. Try reinstalling the bundle.
(dlopen(/Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests, 0x0109): Symbol not found: _$ss7RawSpanVMn
  Referenced from: <74755BC8-9B1F-3A23-B3E7-93B40E7EAB16> /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests
  Expected in:     <26919DE5-6960-3FDC-BBDC-4E6C8C8470B1> /usr/lib/swift/libswiftCore.dylib)
swiftpm_testing_helper/Entrypoint.swift:34: Fatal error: Failed to open test bundle at path /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests: dlopen(/Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests, 0x0101): Symbol not found: _$ss7RawSpanVMn
  Referenced from: <74755BC8-9B1F-3A23-B3E7-93B40E7EAB16> /Users/zane/Downloads/swift-binary-parsing/.build/arm64-apple-macosx/debug/swift-binary-parsingPackageTests.xctest/Contents/MacOS/swift-binary-parsingPackageTests
  Expected in:     <26919DE5-6960-3FDC-BBDC-4E6C8C8470B1> /usr/lib/swift/libswiftCore.dylib
error: Exited with unexpected signal code 5

[natecook1000]

Hi @zaneenders! This library requires access to RawSpan, which is currently limited on macOS to the new beta SDK. It doesn't look like I have the right minimum platform in place on the package yet – I'll get that fixed!

In the meantime, you could try:

• Using the package in a Swift 6.2 container – that's how the CI test runs work: https://github.com/apple/swift-binary-parsing/actions/runs/15574854987/job/43857726692
• Set DYLD_LIBRARY_PATH to the toolchain's path instead of defaulting to the OS

Do either of those approaches work for you?

[zaneenders]

Hi, thank you!

I tried export DYLD_LIBRARY_PATH="/Users/zane/.swiftly/bin/" but that produced the same error. On a different Mac, it works after installing the beta, and it works on an Ubuntu machine. I would just like to avoid installing the beta on my main Mac right now, but would like to experiment with this package and explore how lifetimes work.

➜  swift-binary-parsing git:(main) which swift
/Users/zane/.swiftly/bin/swift

[natecook1000]

Looking at what's in the swiftly path, I don't think it can provide what you need – are you able to try specifying the library path in the actual referenced toolchain? e.g.

export DYLD_LIBRARY_PATH="/Library/Developer/Toolchains/swift-YOUR-SNAPSHOT-HERE-a.xctoolchain/usr/lib/swift/macosx"

[zaneenders]

Thanks for helping me out with this.

I think my system might be a bit misconfigured. This is what's in my Toolchains path despite having my toolchain in XCode set to XCode 16.4 or Dev 2025-06-20.

/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2025-02-24-a.xctoolchain

There is an alias in /Library/Developer/Toolchains of swift-latest.xctoolchain -> /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2025-02-24-a.xctoolchain

That might of been about the last time I tried the main-snapshot 🤔.

[zaneenders]

Ya I reinstalled MacOS 15 and still can't get this to work. just going to wait till the Fall.

Thanks for trying.

[natecook1000]

At some point there should be a compatibility library that includes the span types, to enable this on earlier platforms – will update this thread when I've tested!

[ValentinWalter]

It seems like the compatibility library is now available, but I'm getting Library not loaded: @rpath/libswiftCompatibilitySpan.dylib when trying to run my own package's benchmarks that depend on swift-binary-parsing (both via Xcode 26's xcrun swift build or the equivalent with the latest 6.2 snapshot). Running swift-binary-parsing's own benchmarks works fine though. Is there any special configuration required right now? I thought it might be enabling the "Span" experimental language feature, but that didn't seem to help either.

[ebariaux]

I'm seeing the same error message when trying to run the provide tests on macOS 26 beta 6 with Xcode 26 beta 5 using swift run parser-test Data/PNG/tiny.png as found in the README.md.

Using a 6.2-snapshot-2025-08-13 toolchain on Sequoia 15.6 gives the same error message.

Just adding the swift-binary-parsing dependency to one of my project, without using the module, also results in the same error.

[natecook1000]

I don't know what strange configuration I had locally, but the good news is that after my latest updated I'm seeing this issue as well! Working on getting to the bottom of this…

[hartbit]

Same issue as @ebariaux here using a Xcode 26 beta on Sequoia. What I don't understand @natecook1000 is why you're saying that RawSpan is only available on recent betas? When I check the documentation for the type, it says its available since iOS 12.2+ and macOS 10.14.4.

[hartbit]

By the way, for what it's worth, I have a different error, at build time this time, when compiling from the CLI (with a 6.2 snapshot):

$ swift --version
Apple Swift version 6.2-dev (LLVM 66efdf7c877cecb, Swift 7df1fe7289786ed)
Target: arm64-apple-macosx15.0
Build config: +assertions

$ swift build
...
Undefined symbols for architecture arm64:
  "SwiftSyntax.SyntaxVisitor.(visitationFunc in _F966D2E530B0A562820FA4876E472C28)(for: SwiftSyntax.Syntax) -> (inout SwiftSyntax.Syntax) -> ()", referenced from:
      full type metadata for BinaryParsingMacros.CodeBlockItemVisitor in ParserMacroRewriters.swift.o
      full type metadata for BinaryParsingMacros.HasInoutVisitor in ParserMacroVisitors.swift.o
      full type metadata for BinaryParsingMacros.BBTypeVisitor in ParserMacroVisitors.swift.o
      full type metadata for BinaryParsingMacros.BufferParameterVisitor in ParserMacroVisitors.swift.o
  "SwiftSyntax.SyntaxRewriter.(visitationFunc in _F0C5D882E9301122F145EADC4573BFC8)(for: SwiftSyntax.Syntax) -> (inout SwiftSyntax.Syntax) -> ()", referenced from:
      full type metadata for BinaryParsingMacros.ParsingStatementTransformer in ParserMacroRewriters.swift.o
      full type metadata for BinaryParsingMacros.CodeBlockListRewriter in ParserMacroRewriters.swift.o
  "SwiftSyntax.SyntaxRewriter.__allocating_init(viewMode: SwiftSyntax.SyntaxTreeViewMode, arena: SwiftSyntax.SyntaxArena?) -> SwiftSyntax.SyntaxRewriter", referenced from:
      full type metadata for BinaryParsingMacros.ParsingStatementTransformer in ParserMacroRewriters.swift.o
      full type metadata for BinaryParsingMacros.CodeBlockListRewriter in ParserMacroRewriters.swift.o