Why doesn't Print String appear in my shipping build?

Print String is stripped from Shipping by default. Use UE_LOG with custom log category for diagnostics, or use Development build for visibility.

Print To Screen vs Log?

Print To Screen renders text on viewport (development only). Print To Log writes to log file (always; reachable via output device subscriber).

DECLARE_LOG_CATEGORY_EXTERN(LogMyGame, Log, All); UE_LOG(LogMyGame, Display, TEXT("x = %d"), x). Filter via cmd: log LogMyGame Verbose.

Fix: Print String Not Shown In Shipping Build

Quick answer: Use Development build for Print String. For Shipping, use UE_LOG with a custom category written to log file.

Tester reports a bug; you can’t see Print String in the shipping build. Stripped at compile time.

The Fix

// C++ DECLARE_LOG_CATEGORY_EXTERN in header
DECLARE_LOG_CATEGORY_EXTERN(LogMyGame, Log, All);

// In .cpp
DEFINE_LOG_CATEGORY(LogMyGame);

// At call site
UE_LOG(LogMyGame, Display, TEXT("PlayerHP = %d"), Health);

// Console at runtime
log LogMyGame Verbose

UE_LOG writes to log file in all build types. Custom category lets you filter your messages. Development builds also surface Print String for editor-visible diagnostics.

Verifying

Saved/Logs/<project>.log shows your messages. Console toggles verbosity.

“UE_LOG ships. Print String for dev.”

Related Issues

For DataTable null, see DataTable. For Soft Object cast, see soft object.

UE_LOG ships. Print dev.