R HIGHS Interface

1.15.1-2

• other packages can now use HiGHS from their compiled code through this package: src/highs_ccallable.cpp registers every function of the HiGHS C API (177 at v1.15.1, callbacks included) with R_RegisterCCallable(), and the new header inst/include/highs_ccallable.h provides them under the C API’s own names and signatures, with its constants and callback structs, resolving each through R_GetCCallable() on first use. The list and the header are generated from the bundled highs_c_api.h by tools/gen_ccallable.R (rerun at each HiGHS bump; --check and the tests detect drift). A consumer declares Imports: highs and LinkingTo: highs and includes the header; nothing is linked and the installed size of highs is unchanged. interfaces/highs_c_api.{h,cpp} now ship and build (they were .Rbuildignored; patch_min.R P5 asserts their presence instead of scrubbing them), .Rinstignore is anchored to ^inst/HiGHS(/|$) (the unanchored pattern also dropped inst/include/highs_ccallable.h). Tests in inst/tinytest/test_ccallable.R, including an opt-in (R_HIGHS_LINK_TEST=1) C consumer compiled against the header alone that solves an LP with a logging callback attached
• bundled ‘HiGHS’: apply ERGO-Code/HiGHS#3430 (fix for #3419) through inst/patch_min.R: HVectorBase::packFlag, Highs::standard_form_valid_ and HighsInfoStruct::valid were never initialized; CRAN’s gcc-UBSAN check reports the read of packFlag on every QP solve (“load of value , which is not a valid value for type ‘bool’”). Not yet in a HiGHS release
• bundled ‘HiGHS’: apply ERGO-Code/HiGHS#3472 through inst/patch_min.R: presolve’s dominated-columns pass iterated a row while fixing columns in it, a container overflow that AddressSanitizer reports during MIP presolve. Upstream’s edit, moved to the 1.15.1 location (HPresolve.cpp). Not yet in a HiGHS release
• fix installation failure on CRAN’s r-release-macos-x86_64, r-oldrel-macos-arm64 and r-oldrel-macos-x86_64 (Apple clang 14): cmake’s compiler sanity test is compiled with the force-included src/hi_shim.h but without -std=, and that compiler defaults to gnu++98, where the [[noreturn]] attribute does not parse (“expected expression”); HI_SHIM_NORETURN now expands to [[noreturn]] only for __cplusplus >= 201103L and to __attribute__((noreturn)) otherwise

1.15.1-1

• highs_available_solver_options() now enumerates the bundled library’s own option registry at runtime (Highs::getOptionName()/getOptionType() over all option records via new internal solver_option_registry()) instead of a static table regex-scraped from HighsOptions.h – it can no longer drift from the compiled solver. New advanced column (options registered past HiGHS’s user-settable set, e.g. log_dev_level). Drops pdlp_features_off, a struct member the scrape advertised but HiGHS never registers as an option – it was never actually settable. R/constants.R and inst/parse_highs_options.R are retained for one release as a cross-check (inst/tinytest/test_option-registry.R), then will be removed
• compliance shim gains a thread-local console mute (hi_shim_set_quiet): the Highs constructor banner is silenced for the enumerating instance without capture.output(); worker-thread messages are unaffected
• update bundled HiGHS to v1.15.1
• regenerate R/constants.R from v1.15.1’s HighsOptions.h (156 options; new ones include presolve_rule_test, qp_allow_hot_start, mip_search_simulate_concurrency, simplex_initial_condition_check/ _tolerance, write_matrix_image, write_hessian_image)
• inst/patch_min.R: drop the new unconditional add_subdirectory(extern) (HiGHS >= 1.15 builds a shared highs_extras library by default; the R package needs nothing from extern/)
• .gitmodules: record the actual bundled tag (was stale at v1.9.0)
• hi_new_solver() banner filter extended for v1.15’s second banner line (THIRD_PARTY_NOTICES.md)

1.14.0-3 (development)

• CRAN output/exit compliance reworked from release-time source rewriting to a compile-time shim: src/hi_shim.h is force-included into every bundled HiGHS translation unit (C and C++), remapping printf/stdout/stderr/ abort/exit/… tokens to package-local functions implemented over Rvprintf/REvprintf (src/hi_shim.cpp), with worker-thread messages queued and drained on the R main thread
• new post-build symbol gate tools/audit_symbols.R replicates CRAN’s compiled-code scan on libhighs.a and fails the build on any banned symbol; maintainer-side and OPT-IN (R_HIGHS_SYMBOL_CHECK=strict, set by the Taskfile check targets) – ordinary user/CRAN installs skip it
• inst/patch_highs.R retired to inst/archive/; successor inst/patch_min.R keeps only the structural patches (std::cout rewrite, pdlp/check/examples stubs, cmake surgery) with mandatory match-count assertions – pattern drift now stops the script instead of silently doing nothing
• solver log routing simplified: the deprecated setLogCallback handler is removed; HiGHS’s own console path now lands in Rprintf (sink()- and capture.output()-capturable), still gated by output_flag/log_to_console; the 1024-byte callback truncation is gone
• installed-package size handled declaratively via top-level .Rinstignore (/HiGHS) instead of deleting inst/HiGHS during configure
• -DNDEBUG passed explicitly to the cmake build (previously inherited from HiGHS’s Release default); bundled CMakeLists’ CMAKE_CXX_STANDARD fixed to 17 via patch (HiGHS 1.14 requires C++17)
• inst/tinytest/test_stdout-stderr.R activated: as shipped in 1.14.0-2 its three test functions were defined but never called (0 expectations ran); also fixed its presolve option value (“off”, not FALSE)
• hi_new_solver() strips the HiGHS version banner from captured construction output so warnings carry only their real text

1.14.0-2 2026-06-08 (reconstructed from the CRAN release; fix was not previously in git)

• solver output made controllable/capturable per CRAN request: R_message_handler now receives the solver as callback data and prints only when output_flag is true; hi_solver_run(solver, verbose = FALSE) captures solver log output and returns an integer status code (-1 error / 0 success / 1 warning); highs_solve() gains control$log_to_console
• hi_solver_set_option() accepts non-character scalars (new as_bool() coercion); structure(mat, class = "highs_sparse_matrix") class-attribute fix
• static_cast signed/unsigned cleanups in src/highs_interface.cpp
• new regression test inst/tinytest/test_stdout-stderr.R

1.14 2026-05-18

• update bundled HiGHS to v1.14.0
• regenerate R/constants.R from HighsOptions.h for v1.14.0
• strip CITATION.cff from CMakeLists install target (new in v1.13.1) via inst/patch_highs.R
• HiGHS v1.14.0 requires C++17; bump inst/build_highs.sh accordingly

1.12 2025-11-23

• Thank you to Benjamin Schwendinger for fixing the HighsHashTree.h:855:32: runtime error: index 1 out of bounds for type 'NodePtr [1]' in HiGHS https://github.com/ERGO-Code/HiGHS/pull/2608/commits/c9cbe0b2a283ff0f2aa70a769609ca816189ed0b

1.10 2025-04-20

• update to HiGHS v.10
• improve the low-level API
• improve README

0.1-11 2024-08-03

• update to HiGHS v1.7.2
• improve API