bench: adopt y != y NaN check across stats/base/dists/* C benchmarks

[Planeshifter]

Description

Propagating fixes merged to develop between fe3bacee0 (2026-07-01 12:58 -0700) and c38afb148 (2026-07-01 13:07 -0700) to sibling packages with the same underlying defect.

Pattern: adopt y != y NaN check and drop unneeded <math.h> in C benchmarks

Source commit fe3bacee0 reworked stats/base/dists/anglit/quantile/benchmark/c/benchmark.c to match sibling style. Among those changes, both if ( isnan( y ) ) sites inside static double benchmark( void ) were switched to the tree's canonical y != y self-comparison idiom, and the now-unneeded #include <math.h> was dropped. The identical pair of defects (unnecessary <math.h> include; isnan( y ) NaN check inconsistent with sibling benchmarks) exists in every listed target, and <math.h> carries no other symbol into any of them. Fix applies verbatim per file: one include line deleted, two isnan( y ) occurrences swapped for y != y.

• fe3bacee0 (bench: add missing function documentation and ensure consistency with other benchmarks)
  • @stdlib/stats/base/dists/chi/entropy
  • @stdlib/stats/base/dists/chisquare/kurtosis
  • @stdlib/stats/base/dists/chisquare/mgf
  • @stdlib/stats/base/dists/degenerate/logpmf
  • @stdlib/stats/base/dists/degenerate/pdf
  • @stdlib/stats/base/dists/degenerate/pmf
  • @stdlib/stats/base/dists/degenerate/quantile
  • @stdlib/stats/base/dists/planck/mgf

Related Issues

None.

Questions

No.

Other

Validation

• Search scope: all lib/node_modules/@stdlib/**/benchmark/c/benchmark.c matching isnan( y ); eight sites returned, all under stats/base/dists/*.
• Two independent opus validation passes confirmed at every candidate site that (a) #include <math.h> is present on its own line and carries no other symbol into the file (stdlib headers like stdlib/math/base/special/ceil.h are unrelated), (b) exactly two if ( isnan( y ) ) occurrences exist, both inside static double benchmark( void ) — one inside the ITERATIONS loop, one after — and (c) y is declared double and assigned by the loop's first iteration before the check, so y != y is semantically equivalent to isnan( y ) in all reachable states.
• A sonnet style-consistency pass verified the mechanical patch preserves the include block's contiguous layout and the if ( ... ) single-space padding at both call sites.

Deliberately excluded:

• The remaining stylistic changes from fe3bacee0 (JSDoc scaffolding for static helpers, /** Main execution sequence. */ before int main, inline // TAP plan / // Use the current time to seed the random number generator: comments, i + 1 → i+1): every candidate site already carries most of these, and the missing subsets differ per file. Applying them here would drift into "while we're here" cleanup beyond the propagatable core.
• The two feat: commits from the window (c81fa285 array/filled float16, c38afb148 array/base/getter float16): feature additions, not defect propagations.

Checklist

• Read, understood, and followed the contributing guidelines.

AI Assistance

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

This PR was authored by Claude Code on behalf of @Planeshifter as an automated propagation of fixes merged to develop over the prior 24 hours. Candidate source commits were filtered for generalizable patterns, sibling sites located via grep-able pattern signatures, and each proposed patch independently validated by parallel reviewer agents (two opus validation passes plus a sonnet style-consistency pass) before commits were applied in the primary worktree. A human will audit and promote the PR out of draft.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/chi/entropy	$\\color{green}166/166$ $\\color{green}+100.00\\%$	$\\color{green}8/8$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}166/166$ $\\color{green}+100.00\\%$
stats/base/dists/chisquare/kurtosis	$\\color{green}161/161$ $\\color{green}+100.00\\%$	$\\color{green}8/8$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}161/161$ $\\color{green}+100.00\\%$
stats/base/dists/chisquare/mgf	$\\color{green}259/259$ $\\color{green}+100.00\\%$	$\\color{green}19/19$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}259/259$ $\\color{green}+100.00\\%$
stats/base/dists/degenerate/logpmf	$\\color{green}249/249$ $\\color{green}+100.00\\%$	$\\color{green}19/19$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}249/249$ $\\color{green}+100.00\\%$
stats/base/dists/degenerate/pdf	$\\color{green}249/249$ $\\color{green}+100.00\\%$	$\\color{green}19/19$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}249/249$ $\\color{green}+100.00\\%$
stats/base/dists/degenerate/pmf	$\\color{green}247/247$ $\\color{green}+100.00\\%$	$\\color{green}19/19$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}247/247$ $\\color{green}+100.00\\%$
stats/base/dists/degenerate/quantile	$\\color{green}266/266$ $\\color{green}+100.00\\%$	$\\color{green}18/18$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}266/266$ $\\color{green}+100.00\\%$
stats/base/dists/planck/mgf	$\\color{green}252/252$ $\\color{green}+100.00\\%$	$\\color{green}17/17$ $\\color{green}+100.00\\%$	$\\color{green}4/4$ $\\color{green}+100.00\\%$	$\\color{green}252/252$ $\\color{green}+100.00\\%$

The above coverage report was generated for the changes in this PR.