Fix assertion failure in ILDasm with -METADATA=RAW flag

[Copilot]

Description

ILDasm crashes with assertion failure when invoked with -METADATA=RAW:

ASSERT FAILED
    Expression: ARRAY_SIZE(g_szMapElementType) == ELEMENT_TYPE_MAX
    Location:   line 256 in src/coreclr/tools/metainfo/mdinfo.cpp

The g_szMapElementType and g_szMapUndecorateType arrays had 34 elements but ELEMENT_TYPE_MAX is 0x23 (35). Missing entry: ELEMENT_TYPE_CMOD_INTERNAL at index 0x22.

Added "CMOD_INTERNAL" to both arrays in mdinfo.cpp.

Customer Impact

ILDasm with -METADATA=RAW flag fails immediately on any assembly. Blocks metadata inspection workflows.

Regression

Yes. ELEMENT_TYPE_CMOD_INTERNAL was added to corhdr.h but corresponding array entries were not updated.

Testing

• Built CoreCLR successfully
• Verified ILDasm with -METADATA=RAW completes without assertion on test assembly

Risk

Low. Two-line fix adds missing array element to match enum definition. No logic changes.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Assert when passing -METADATA=RAW to ILDasm.</issue_title>
<issue_description>runtime/artifacts/bin/coreclr/osx.arm64.Debug/ildasm -ALL -METADATA=RAW Test.dll > out.txt
ASSERT FAILED
Expression: ARRAY_SIZE(g_szMapElementType) == ELEMENT_TYPE_MAX
Location: line 256 in .../runtime/src/coreclr/ildasm/../tools/metainfo/mdinfo.cpp
Function: MDInfo
Process: 36920
zsh: trace trap runtime/artifacts/bin/coreclr/osx.arm64.Debug/ildasm -ALL -METADATA=RAW</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Assert when passing -METADATA=RAW to ILDasm. #122875

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[Copilot]

Pull request overview

This PR fixes an assertion failure that occurs when running ILDasm with the -METADATA=RAW flag. The root cause was a size mismatch between the g_szMapElementType and g_szMapUndecorateType arrays (which had 34 elements) and the expected size ELEMENT_TYPE_MAX (which is 0x23 or 35 decimal). The missing element was ELEMENT_TYPE_CMOD_INTERNAL at index 0x22.

Key changes:

• Added ELEMENT_TYPE_CMOD_INTERNAL entry to both mapping arrays in mdinfo.cpp to match the complete CorElementType enum
• Modified assertion format in pal_assert.h to reorder filename and line number display

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/coreclr/tools/metainfo/mdinfo.cpp	Adds missing "CMOD_INTERNAL" entry at index 0x22 to both g_szMapElementType and g_szMapUndecorateType arrays, fixing the array size to match ELEMENT_TYPE_MAX (35 elements)
src/coreclr/pal/inc/pal_assert.h	Reorders __FILE__ and __LINE__ parameters in assertion output format from "line %d in %s" to "%s:%d"

[AaronRobinsonMSFT]

@jkoritzinsky Looks like we missed updating ILDasm when adding ELEMENT_TYPE_CMOD_INTERNAL in #106424.

[AaronRobinsonMSFT]

/ba-g Unrelated