To run the full test suite after compiling and installing djbsort, run djbsort-fulltest. This indicates success in two ways: it prints full tests succeeded as its last line of output; it exits 0.

Any change in the compiled library (compiling for a different architecture, compiling with a different compiler, etc.) must be subjected to a new round of tests. A compiled version of djbsort that does not pass the full test suite is not supported.

One run of djbsort-fulltest was observed to take 39 core-minutes on cezanne (AMD Ryzen 5 PRO 5650G; 6 cores, 2 threads/core) with overclocking disabled (so running at 3.9GHz). This test finished in under 4 minutes of real time; djbsort-fulltest includes some automatic parallelization. To limit the number of threads used to 1, run env THREADS=1 djbsort-fulltest.

djbsort automatically selects AVX2 implementations when it is running on an Intel/AMD CPU that supports AVX2, while falling back to portable implementations otherwise. Running djbsort-fulltest on an Intel/AMD CPU without AVX2 will say CPU does not support implementation for the AVX2 implementations and will fail. To test a compilation of djbsort for Intel/AMD CPUs, you have to run djbsort-fulltest on an Intel/AMD CPU with AVX2.

The rest of this page says more about what is happening inside djbsort-fulltest.

Conventional tests

The workhorse inside djbsort-fulltest is a separate djbsort-test program.

Simply calling djbsort-test without arguments will run various tests on the subroutines in djbsort, and will indicate success in two ways: printing all tests succeeded as the last line of output, and exiting 0.

For parallelism, djbsort-fulltest calls djbsort-test many times, using optional djbsort-test arguments to narrow what is being tested in each call.

Data-flow tests

Another way that djbsort-fulltest runs djbsort-test is as follows, running TIMECOP-style tests that branch conditions and array indices are independent of secrets:

env valgrind_multiplier=1 \
valgrind -q \
--error-exitcode=99 \
djbsort-test

This requires valgrind to be installed at test time. The output will include a line valgrind 1 declassify 1 if the library was compiled with --valgrind (which is the only supported option), or a line valgrind 1 declassify 0 (expect false positives) otherwise.

These data-flow tests do not supersede the conventional tests. The conventional tests run code directly on the CPU and might catch issues hidden by the emulation in valgrind. The conventional tests also include some memory tests that are disabled to improve the valgrind memory tests but that are not necessarily superseded by the valgrind memory tests.

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Version: This is version 2026.01.26 of the "Test" web page.