---
title: "Undefined Symbols Error"
canonical_url: "https://www.nutrient.io/guides/ios/usage-issues/undefined-symbols-error/"
md_url: "https://www.nutrient.io/guides/ios/usage-issues/undefined-symbols-error.md"
last_updated: "2026-05-15T19:10:05.040Z"
description: "Solutions for common issues and errors in Nutrient iOS SDK with debugging tips and workarounds."
---

You might get the following output when integrating PSPDFKit:

```

Undefined symbols for architecture i386:

"operator delete(void*)", referenced from:
___PSPDFInvokeRuntimePatches_block_invoke in PSPDFKit(PSPDFPatches.o)
"operator new(unsigned long)", referenced from:
___PSPDFInvokeRuntimePatches_block_invoke in PSPDFKit(PSPDFPatches.o)
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)

```

If you do, it means you’re missing the `-lc++` linker flag that has been required since PSPDFKit 4.2.0.

See the [Integrating PSPDFKit](https://www.nutrient.io/sdk/ios/getting-started.md) guide for details.
---

## Related pages

- [Version String Enforcements](/guides/ios/announcements/version-string-enforcements.md)
- [Incorrect Bundle Version](/guides/ios/faq/incorrect-bundle-version.md)
- [Error 999](/guides/ios/pspdfkit-instant/error-999.md)
- [Sqlite Warnings](/guides/ios/troubleshooting/sqlite-warnings.md)
- [Pspdfkitbundle Issues](/guides/ios/configuration-issues/pspdfkitbundle-issues.md)