-`ENABLE_GMP_STATIC`: Does static linking against gmp. The default is `OFF`.
-`GMP_BUILD_CONFIG_ARGS`: Provides additional config arguments for the gmp build (for example `--disable-assembly`). By default, no config arguments are provided.
If set to `MINI`, the mini-gmp library is used, whose sources are included in the repository, in the folder `src/mini-gmp`. In this case, no copies of the full gmp library (system or custom-built) are required.
Can be used to specify special build types. The options are:
-`Release`: Builds with optimizations enabled and assertions disabled.
-`Debug`: Builds with debug symbols.
-`ASAN`: Builds with AddressSanitizer memory error detector.
-`MSAN`: Builds with MemorySanitizer detector for uninitialized reads.
-`LSAN`: Builds with LeakSanitizer for run-time memory leak detection.
-`UBSAN`: Builds with UndefinedBehaviorSanitizer for undefined behavior detection.
The default build type uses the flags `-O3 -Wstrict-prototypes -Wno-error=strict-prototypes -fvisibility=hidden -Wno-error=implicit-function-declaration -Wno-error=attributes`. (Notice that assertions remain enabled in this configuration, which harms performance.)
The benchmarks profile the key generation, signature and verification functions. The results are reported in CPU cycles if available on the host platform, and timing in nanoseconds otherwise.
Verification routines are supported in 32-bit embedded architectures running on bare metal environments such as the ARM Cortex-M4, but they are not directly supported by the build system of the present repository. The [pqm4 project](https://github.com/mupq/pqm4) is supported for evaluating SQIsign verification in the ARM Cortex-M4.
pqm4 assumes that the full NIST API (keypair generation, signing and verification) is available. Since only verification is supported, the remaining routines are mocked and must meet certain constraints, such as sharing the public key, signing a prespecified message and being of a specific size used by the testing and benchmarking binaries of pqm4. Therefore, additional KATs must be generated specifically for pqm4, which is done by a dedicated KAT generator for pqm4, found in `apps/PQCgenKAT_sign_pqm4.c`.
A copy of the most recent version of pqm4 as of the round 2 submission deadline, including an implementation of SQIsign verification generated directly from this repository using the procedure explained next, is made available [here](https://github.com/SQISign/the-sqisign-pqm4), in the `sqisign` branch.
If changes are made to the library, the `scripts/gen_pqm4_sources.sh` shell script can be run, from the root folder of the repository, to generate a pqm4-compatible folder structure in `src/pqm4/sqisign_lvl{1,3,5}`, which can then be copied to the `crypto_sign` folder of pqm4. Note that the pqm4 KAT generator is automatically run by this script.
