[Dwite]

Problem

Custom markers can crash on iOS when an application consumes the published core 0.9.1 library with Compose Multiplatform 1.12.0:

kotlin.internal.IrLinkageError: Function 'encodeToData' can not be called:
No function found for symbol 'org.jetbrains.skia/Image.encodeToData|
encodeToData(org.jetbrains.skia.EncodedImageFormat;kotlin.Int){}[0]'

The failing path is ImageBitmap.toUIImage() in Extensions.kt. The older precompiled Kotlin/Native library references the previous Skia signature. Recompiling the existing source against Compose 1.12 resolves that call without changing marker behavior.

Changes

• Upgrade Compose to 1.12.0 and Kotlin to 2.4.0.
• Upgrade Coroutines to 1.11.0 and declare it in core. Strict linking with 1.10.2 exposes references to the old SubclassOptInRequired constructor.
• Fail framework linking on partial-linkage errors.
• Remove the unsupported iosX64 target and obsolete native-cache properties.
• Add an iOS test that executes the custom-marker bitmap conversion, and run it in CI.

Validation

• Reproduced the exact encodeToData error with a separate iOS simulator test consuming the published 0.9.1 binary and Compose 1.12.0.
• The same test passes with this source build (1 test, 0 failures).
• Passed :kmp-maps:core:linkDebugFrameworkIosSimulatorArm64 with strict partial linkage.
• Passed :kmp-maps:core:compileDebugKotlinAndroid.
• Passed :kmp-maps:core:linkReleaseFrameworkIosArm64 with strict partial linkage.
• Passed :kmp-maps:core:compileKotlinJvm, :kmp-maps:google-maps:compileDebugKotlinAndroid, and :kmp-maps:google-maps:compileKotlinJvm.
• Google Maps iOS integration has not been validated locally.

This requires a new library publication before downstream applications can consume the rebuilt binaries.

[BrandonSmith]

We would love for this PR to land soon. For now, we have to fork and publish locally in our CI flow to get kmp-maps working.

This is currently a blocker for us as well, so getting this merged and released would save us from maintaining our own fork. Thanks for the work on this!