dotnet/runtime · critical

Error: Fail to PAL_Initialize

Error message

Error: Fail to PAL_Initialize

What it means

On Unix (TARGET_UNIX) the ilasm `main` calls PAL_Initialize to bootstrap the Platform Abstraction Layer before doing anything (main.cpp:884). A nonzero return means the PAL could not initialize the runtime environment (threading, locale, file system, etc.); ilasm prints this and `exit(1)` immediately. No assembly work happens.

Source

Thrown at src/coreclr/ilasm/main.cpp:886

            printf("               Fixup and linking         %d\n",(int)(cw.cFilegenBegin - cw.cMDEmitEnd));
            printf("               CEE file generation       %d\n",(int)(cw.cFilegenEnd - cw.cFilegenBegin));
            printf("               PE file writing           %d\n",(int)(cw.cEnd - cw.cFilegenEnd));
        }
    }
    else
    {
        printf("\n***** FAILURE ***** \n");
    }
    exit(exitval);
    return exitval;
}

#ifdef TARGET_UNIX
int main(int argc, char* str[])
{
    if (0 != PAL_Initialize(argc, str))
    {
        fprintf(stderr,"Error: Fail to PAL_Initialize\n");
        exit(1);
    }

    WCHAR **argv = new WCHAR*[argc];
    for (int i = 0; i < argc; i++) {
        int length = MultiByteToWideChar(CP_ACP, 0, str[i], -1, NULL, 0);
        ASSERTE_ALL_BUILDS(length != 0);

        LPWSTR result = new (nothrow) WCHAR[length];
        ASSERTE_ALL_BUILDS(result != NULL);

        length = MultiByteToWideChar(CP_ACP, 0, str[i], -1, result, length);
        ASSERTE_ALL_BUILDS (length != 0);

        argv[i] = result;
    }

    int ret = wmain(argc, argv);

View on GitHub (pinned to 290d5ab72c)

Solutions

1. Reinstall the .NET/CoreCLR SDK so the PAL libraries match the ilasm binary.
2. Clear or correct LD_LIBRARY_PATH so the bundled PAL libs are found.
3. Run on a supported OS/glibc version for that ilasm build.

Example fix

# before: mismatched runtime
LD_LIBRARY_PATH=/opt/oldlibs ilasm foo.il   # Error: Fail to PAL_Initialize
# after
unset LD_LIBRARY_PATH && /usr/share/dotnet/ilasm foo.il

# Verify the PAL libraries resolve before running ilasm.
if ! ldd "$(command -v ilasm)" | grep -qi 'libclr.*pal\|libcoreclrpal'; then
  echo 'PAL libraries unresolved; install will fail to PAL_Initialize'; exit 1
fi

When it happens

Trigger: Running an ilasm binary whose PAL runtime files are missing or wrong version; a corrupted install; a host OS/glibc incompatible with the bundled PAL.

Common situations: Copying an ilasm binary without its runtime directory; running on an unsupported distro/glibc; LD_LIBRARY_PATH shadowing the PAL libraries.

Related errors

• Failed to initialize Assembler
• Failed on mono_wasm_get_dbg_command_info
• Failed to initialize ICU data
• Mismatched git hashes between loader and runtime. Loader: ${
• Invalid runtime config, cannot initialize the runtime.

AI-assisted analysis of dotnet/runtime@290d5ab72c (2026-08-06). Data as JSON: /api/errors/ffdd85a13bd2d8e6. Report an issue: GitHub.