Skip to content

[browser][coreclr] TypeError: (Module.preRun || []) is not iterable #132555

New issue
New issue
Closed
#134642
#134527
Closed
[browser][coreclr] TypeError: (Module.preRun || []) is not iterable#132555
#134642
#134527
Assignees
pavelsavara
Labels
arch-wasmWebAssembly architecturearea-System.Runtime.InteropServices.JavaScriptos-browserBrowser variant of arch-wasm
Milestone
12.0.0

Description

@maraf
maraf
opened on Aug 20, 2026

Raised on #132478 (log) when migrated CoreCLR Wasm.Build.Tests to standard workload.

[error] DOTNET: Unhandled error:  (Module.preRun || []) is not iterable
TypeError: (Module.preRun || []) is not iterable
    at Object.dotnetInitializeModule (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:71378)
    at Object.selfInitialize (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:70132)
    at createDotnetRuntime (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:111050)
    at Module.dotnetInitializeModule (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:18:12)
    at Fe (http://127.0.0.1:44895/_framework/dotnet.u8pojv2t7z.js:5:26906)
    at async Object.create (http://127.0.0.1:44895/_framework/dotnet.u8pojv2t7z.js:5:32740)
    at async http://127.0.0.1:44895/main.js:281:106
[info] DOTNET: Aborting startup, reason: TypeError: (Module.preRun || []) is not iterable
Exited with 1
[log] WASM EXIT 1
[ERROR] PageError: TypeError: (Module.preRun || []) is not iterable
    at Object.dotnetInitializeModule (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:71378)
    at Object.selfInitialize (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:70132)
    at createDotnetRuntime (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:111050)
    at Module.dotnetInitializeModule (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:18:12)
    at Fe (http://127.0.0.1:44895/_framework/dotnet.u8pojv2t7z.js:5:26906)
    at async Object.create (http://127.0.0.1:44895/_framework/dotnet.u8pojv2t7z.js:5:32740)
    at async http://127.0.0.1:44895/main.js:281:106
Browser has been disconnected
    Wasm.Build.Tests.MemoryTests.AllocateLargeHeapThenRepeatedlyInterop [FAIL]
      System.Exception : Expected exit code 0 but got 1.
      consoleOutput=DOTNET: Unhandled error:  (Module.preRun || []) is not iterable
      TypeError: (Module.preRun || []) is not iterable
          at Object.dotnetInitializeModule (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:71378)
          at Object.selfInitialize (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:70132)
          at createDotnetRuntime (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:1:111050)
          at Module.dotnetInitializeModule (http://127.0.0.1:44895/_framework/dotnet.native.0ywy2ly7o4.js:18:12)
          at Fe (http://127.0.0.1:44895/_framework/dotnet.u8pojv2t7z.js:5:26906)
          at async Object.create (http://127.0.0.1:44895/_framework/dotnet.u8pojv2t7z.js:5:32740)
          at async http://127.0.0.1:44895/main.js:281:106
      DOTNET: Aborting startup, reason: TypeError: (Module.preRun || []) is not iterable
      Stack Trace:
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(570,0): at Wasm.Build.Tests.WasmTemplateTestsBase.BrowserRun(ToolCommand cmd, String runArgs, RunOptions runOptions)
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(572,0): at Wasm.Build.Tests.WasmTemplateTestsBase.BrowserRun(ToolCommand cmd, String runArgs, RunOptions runOptions)
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(513,0): at Wasm.Build.Tests.WasmTemplateTestsBase.BrowserRunTest(String runArgs, String workingDirectory, RunOptions runOptions)
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(484,0): at Wasm.Build.Tests.WasmTemplateTestsBase.BrowserRun(RunOptions runOptions)
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(470,0): at Wasm.Build.Tests.WasmTemplateTestsBase.RunForBuildWithDotnetRun(RunOptions runOptions)
        /_/src/mono/wasm/Wasm.Build.Tests/MemoryTests.cs(46,0): at Wasm.Build.Tests.MemoryTests.AllocateLargeHeapThenRepeatedlyInterop()

Activity

  1. maraf
    added this to the 12.0.0 milestone on Aug 20, 2026
  2. maraf
    assigned
    pavelsavara
    on Aug 20, 2026
  3. maraf
    added
    arch-wasmWebAssembly architecture
    area-System.Runtime.InteropServices.JavaScript
    os-browserBrowser variant of arch-wasm
    on Aug 20, 2026

  4. dotnet-policy-service commented on Aug 20, 2026

    @dotnet-policy-service
    dotnet-policy-serviceBot
    on Aug 20, 2026 – with Dotnet Policy Service
    Contributor

    Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
    See info in area-owners.md if you want to be subscribed.

  5. pavelsavara
    added a commit that references this issue on Sep 23, 2026

    Accept the function form of Module.preInit and Module.preRun on CoreCLR

    8370487
  6. pavelsavara
    closed this as completedin #134527on Sep 30, 2026
  7. github-actions
    locked and limited conversation to collaborators on Oct 30, 2026
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Metadata

Metadata

Assignees

Labels

arch-wasmWebAssembly architecturearea-System.Runtime.InteropServices.JavaScriptos-browserBrowser variant of arch-wasm

Type

No type

Projects

No projects

    Milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions