Using `String` in Embedded Swift mode reports missing symbols when using Strings as keys to dictionaries

[phausler]

Description

Using String as a key to a dictionary results in missing symbols with no explained way to resolve:

ld.lld: error: undefined hidden symbol: _swift_stdlib_getNormData
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss16_StringGutsSliceV17_withNFCCodeUnitsyyys5UInt8VKXEKF)
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFDNormalizerV7_resume9consumingAB6ScalarV6scalar_AB9_NormDataV04normH0tSgAHSgyXE_tF)
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFDNormalizerV13decomposeSlow33_B136021ACF5AAEFA178D70CE67C7EEF0LLyyAB6ScalarV6scalar_AB9_NormDataV04normO0t_tF)
>>> referenced 6 more times

ld.lld: error: undefined hidden symbol: _swift_stdlib_getComposition
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFCNormalizerV7_resume12consumingNFDAB6ScalarVSgAH6scalar_AB9_NormDataV04normI0tSgADzXE_tF)
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFCNormalizerV7_resume12consumingNFDAB6ScalarVSgAH6scalar_AB9_NormDataV04normI0tSgADzXE_tF)
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFCNormalizerV7_resume12consumingNFDAB6ScalarVSgAH6scalar_AB9_NormDataV04normI0tSgADzXE_tF.110)
>>> referenced 1 more times

ld.lld: error: undefined hidden symbol: _swift_stdlib_getDecompositionEntry
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFDNormalizerV13decomposeSlow33_B136021ACF5AAEFA178D70CE67C7EEF0LLyyAB6ScalarV6scalar_AB9_NormDataV04normO0t_tF)

ld.lld: error: undefined hidden symbol: _swift_stdlib_nfd_decompositions
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFDNormalizerV13decomposeSlow33_B136021ACF5AAEFA178D70CE67C7EEF0LLyyAB6ScalarV6scalar_AB9_NormDataV04normO0t_tF)
>>> referenced by ld-temp.o
>>>               lto.tmp:($ss7UnicodeO14_NFDNormalizerV13decomposeSlow33_B136021ACF5AAEFA178D70CE67C7EEF0LLyyAB6ScalarV6scalar_AB9_NormDataV04normO0t_tF)

Reproduction

var table: [String: Int] = [:]
table["foo"] = 1382

Expected behavior

at least there should be some description on how to link the NFD/NFC tables

Environment

Swift version 6.0-dev (LLVM 4ee06774aa7ace9, Swift 2944529)
Target: aarch64-none-none-elf

Additional information

No response

[oleksandr-kosylov]

+1
using Visual Studio Code + CMake 3.31.0, can't find a way to link tables.a

When I explicitly use ld - looks like ld doesn't know anything about riscv32-none-none-eabi arch (in my case).

[oleksandr-kosylov]

Here is how I workarounded the problem:

I added sources into my project so symbols got built within main target.
Here is a list of files I used:

Headers

1. CaseData.h
2. GraphemeData.h
3. NormalizationData.h
4. ScalarPropsData.h
5. ScriptData.h
6. SwiftStdbool.h
7. SwiftStdint.h
8. UnicodeData.h

Sources

1. UnicodeData.cpp
2. UnicodeGrapheme.cpp
3. UnicodeNormalization.cpp
4. UnicodeScalarProps.cpp

You may want to update/remove swift-specific macro in sources, but it's shouldn't be a problem.
So finally I've got string APIs working on esp32-riskv.

CC @phausler

Hope this helps.
Thanks!

[nonameplum]

@oleksandr-kosylov could you give more insights? From where you got *.cpp files and where have you put *.h files and *.cpp files?

[oleksandr-kosylov]

Hello @nonameplum , I used sources from official swift repo - https://github.com/swiftlang/swift.
I've added cpps as sources in CMakeLists and finally included .h files into bridging header file.