bundle_compactKeys(%s) or bundle_getKeyBytes() failed: %s

Error message

bundle_compactKeys(%s) or bundle_getKeyBytes() failed: %s

What it means

During pool bundle generation (--write-pool-bundle mode), genrb calls compactKeys() to deduplicate key strings and getKeyBytes() to retrieve the compacted key bytes. If either call sets a UErrorCode failure, the pool bundle cannot be assembled. Pool bundles are a shared-key optimization that reduces total .res file size across a locale set.

Source

Thrown at deps/icu-small/source/tools/genrb/genrb.cpp:728

        }

        if (isVerbose()) {
            filter.print(std::cout);
        }

        // Apply the filter to the data
        ResKeyPath path;
        data->fRoot->applyFilter(filter, path, data.getAlias());
    }

    if(options[WRITE_POOL_BUNDLE].doesOccur) {
        data->fWritePoolBundle = newPoolBundle;
        data->compactKeys(status);
        int32_t newKeysLength;
        const char *newKeys = data->getKeyBytes(&newKeysLength);
        newPoolBundle->addKeyBytes(newKeys, newKeysLength, status);
        if(U_FAILURE(status)) {
            fprintf(stderr, "bundle_compactKeys(%s) or bundle_getKeyBytes() failed: %s\n",
                    filename, u_errorName(status));
            return;
        }
        /* count the number of just-added key strings */
        for(const char *newKeysLimit = newKeys + newKeysLength; newKeys < newKeysLimit; ++newKeys) {
            if(*newKeys == 0) {
                ++newPoolBundle->fKeysCount;
            }
        }
    }

    if(options[USE_POOL_BUNDLE].doesOccur) {
        data->fUsePoolBundle = &poolBundle;
    }

    /* Determine the target rb filename */
    uprv_free(make_res_filename(filename, outputDir, packageName, status));
    if(U_FAILURE(status)) {

View on GitHub (pinned to 1b2de5e052)

Solutions

Check the u_errorName code in the message — U_MEMORY_ALLOCATION_ERROR indicates memory pressure, U_BUFFER_OVERFLOW_ERROR indicates too many keys
Reduce the number of unique top-level keys in the resource bundles fed to the pool bundle build
Build with fewer simultaneous parallel genrb processes to reduce memory pressure
If the issue is a key table size limit, split the locale data into multiple pool bundles
Disable pool bundle mode (--write-pool-bundle) if the optimization is not critical for your use case

Defensive patterns

Strategy: validation

Validate before calling

# Before building with --write-pool-bundle, check available memory and key count
free -h
# Estimate unique keys across all locale bundles that will be pooled
grep -ohP '^\s*\w+\s*\{' all_locales/*.txt | sort -u | wc -l

Prevention

Monitor memory usage during pool bundle builds and set appropriate parallelism limits
Keep the number of unique keys per locale set reasonable to stay within pool bundle limits
Build pool bundles separately from regular locale builds to isolate failures
Check the ICU documentation for pool bundle key limits for your ICU version

When it happens

Trigger: Running genrb with the --write-pool-bundle option on a resource bundle whose key set causes compactKeys() to fail — typically due to an internal key table overflow, hash collision limit, or memory exhaustion during key compaction. The newPoolBundle->addKeyBytes() call can also trigger this if the key byte buffer exceeds capacity.

Common situations: Building ICU data with pool bundle optimization enabled on a very large locale set; using a custom resource bundle with an unusually high number of unique keys; memory pressure during a parallel build of many locales.

Related errors

AI-assisted analysis of nodejs/node@1b2de5e052 (2026-08-13). Data as JSON: /api/errors/c71853e68fc160a1. Report an issue: GitHub.