math: compile FP-free with BND_MATH_NO_FP (incl. the single header)#5
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Add BND_MATH_NO_FP: when set, the double (FP) engine and its <cmath> include compile out entirely, leaving the always-present integer/CORDIC engine to serve the full bnd::math API. The public surface, output grids, and types are unchanged — only the compute backend differs. Implied by BND_MATH_FIXED and auto-enabled on freestanding targets (__STDC_HOSTED__ == 0). - cmath_double.hpp resolves BND_MATH_NO_FP and gates <cmath> + the entire dbl engine behind it. The guard is at conditional depth, so the amalgamator keeps the <cmath> include inline under the same #ifndef — the SINGLE HEADER honors the FP-free path identically to the modular headers. - cmath.hpp dispatch and the constexpr BND_MATH_FN macro key on BND_MATH_NO_FP (every dbl:: reference already sat in the #else branch), so the integer engine is selected and constexpr whenever FP is unavailable. - New single_header_nofp_smoke target + CI step (Linux): compiles the single header with BND_MATH_NO_FP and a poison <cmath> shim placed first on the include path, so the build hard-errors if any <cmath> is pulled in. Verified it fires without the macro (genuine proof) and passes with it. - docs/math.md: document the FP-free build. Verified: default 397/397, CORDIC 440/440, nofp smoke builds+runs FP-free. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Phase 2 of the math-engine plan — the FP-free guard
Lets the library (and the single header) compile with no hardware floating point and no
<cmath>, leaving the always-present integer/CORDIC engine to serve the fullbnd::mathAPI. The public surface, output grids, and types are unchanged — only the compute backend differs.What
BND_MATH_NO_FPdoes#include <cmath>out entirely.BND_MATH_FIXED; auto-enabled when__STDC_HOSTED__ == 0(-ffreestanding).constexprunder it (the integer engine).How it works
cmath_double.hppresolves the macro and gates<cmath>+ the wholedblengine behind#ifndef BND_MATH_NO_FP. The guard is at conditional depth, so the amalgamator keeps the<cmath>include inline under the same guard — the single header honors the FP-free path identically to the modular headers (no longer hoisted unconditionally to the top).constexpr BND_MATH_FNmacro incmath.hppkey onBND_MATH_NO_FP. Everydbl::reference already sat in an#elsebranch, so the integer engine is selected cleanly.Proof (not just "it compiles")
New
single_header_nofp_smoketarget + Linux CI step compiles the single header with-DBND_MATH_NO_FPand a poison<cmath>shim first on the include path — the build hard-errors if any<cmath>is pulled in. Confirmed locally that it fires without the macro (genuine) and passes with it.Verification
single_header_nofp_smokebuilds & runs FP-free;single_header_smoke/single_header_freestanding_smokestill buildamalgamate_up_to_dategreen🤖 Generated with Claude Code