[embedded] [IRGen] Avoid creating "aliases" for type metadata address points in client modules#87045
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aschwaighofer merged 1 commit intoswiftlang:mainfrom Feb 7, 2026
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… points in client modules
We don't need to export the type metadata address point alias in clients that
lazily emit other module's type metadata. There will be an exported
metadata symbol in the originating module for that purpose.
Instead, satisfy any local uses of the metadata address point uses by its
underlying address computation.
This is to workaround a bug where LLVM generates the wrong assembly for
weak aliases that point to an offset of another symbol.
```
@"$e1C7MyClassCySiGN" = weak_odr hidden alias %swift.type, getelementptr
inbounds (<{ ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr }>,
ptr @"$e1C7MyClassCySiGMf", i32 0, i32 1)
```
Generates:
```
.weak_reference _$e1C7MyClassCySiGN
.private_extern _$e1C7MyClassCySiGN
.alt_entry _$e1C7MyClassCySiGN
_$e1C7MyClassCySiGN = _$e1C7MyClassCySiGMf+8
```
Instead of
```
.weak_definition _$e1C7MyClassCySiGN
.private_extern _$e1C7MyClassCySiGN
.alt_entry _$e1C7MyClassCySiGN
_$e1C7MyClassCySiGN = _$e1C7MyClassCySiGMf+8
```
Leading for "weak"ness to be ignored and duplicate type medata symbol linkage
errors.
rdar://169573918
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We don't need to export the type metadata address point alias in clients that lazily emit other module's type metadata. There will be an exported metadata symbol in the originating module for that purpose.
Instead, satisfy any local uses of the metadata address point uses by its underlying address computation.
This is to workaround a bug where LLVM generates the wrong assembly for weak aliases that point to an offset of another symbol.
Generates:
Instead of
Leading for "weak"ness to be ignored and duplicate type medata symbol linkage errors.
rdar://169573918