From 2cbd6980e5a06ce4a2828a10b6cdb0efba827f84 Mon Sep 17 00:00:00 2001
From: mihael <hi@mihaelm.com>
Date: Fri, 20 Mar 2026 17:44:23 +0100
Subject: [PATCH] `libzigc/math`: Implement `finite`, `finitef`

The behaviour of `libc` `finite` functions is the same as Zig std's, so
the function basically delegates to `math.isFinite` and no new tests were
added. These functions are obsolete, but still part of `musl`.

No results are attached in this case as `libc-test` doesn't have tests for them.
---
 lib/c/math.zig                   | 10 ++++++++++
 lib/libc/musl/src/math/finite.c  |  7 -------
 lib/libc/musl/src/math/finitef.c |  7 -------
 src/libs/musl.zig                |  2 --
 src/libs/wasi_libc.zig           |  2 --
 5 files changed, 10 insertions(+), 18 deletions(-)
 delete mode 100644 lib/libc/musl/src/math/finite.c
 delete mode 100644 lib/libc/musl/src/math/finitef.c

diff --git a/lib/c/math.zig b/lib/c/math.zig
index 1f80e1cc7e5362891884988ecff8423269bf9ce8..36bdfcfa753e66d3506beefccb7484f8260a3747 100644
--- a/lib/c/math.zig
+++ b/lib/c/math.zig
@@ -62,6 +62,8 @@ comptime {
         symbol(&exp10, "exp10");
         symbol(&exp10f, "exp10f");
         symbol(&fdim, "fdim");
+        symbol(&finite, "finite");
+        symbol(&finitef, "finitef");
         symbol(&frexp, "frexp");
         symbol(&hypot, "hypot");
         symbol(&modf, "modf");
@@ -164,6 +166,14 @@ fn fdim(x: f64, y: f64) callconv(.c) f64 {
     return 0;
 }
 
+fn finite(x: f64) callconv(.c) c_int {
+    return if (math.isFinite(x)) 1 else 0;
+}
+
+fn finitef(x: f32) callconv(.c) c_int {
+    return if (math.isFinite(x)) 1 else 0;
+}
+
 fn frexpGeneric(comptime T: type, x: T, e: *c_int) T {
     // libc expects `*e` to be unspecified in this case; an unspecified C value
     // should be a valid value of the relevant type, yet Zig's std
diff --git a/lib/libc/musl/src/math/finite.c b/lib/libc/musl/src/math/finite.c
deleted file mode 100644
index 25a0575fb9757d6ddaec5a538db7984d007fdb55..0000000000000000000000000000000000000000
--- a/lib/libc/musl/src/math/finite.c
+++ /dev/null
@@ -1,7 +0,0 @@
-#define _GNU_SOURCE
-#include <math.h>
-
-int finite(double x)
-{
-	return isfinite(x);
-}
diff --git a/lib/libc/musl/src/math/finitef.c b/lib/libc/musl/src/math/finitef.c
deleted file mode 100644
index 2c4c771463a1b244244edf3ea92026f8fe78c67a..0000000000000000000000000000000000000000
--- a/lib/libc/musl/src/math/finitef.c
+++ /dev/null
@@ -1,7 +0,0 @@
-#define _GNU_SOURCE
-#include <math.h>
-
-int finitef(float x)
-{
-	return isfinite(x);
-}
diff --git a/src/libs/musl.zig b/src/libs/musl.zig
index 73f93a82710d735f2b7998d27811c2d2be2dc0c9..c451312bbb9d39620f92364b173df38bc499e795 100644
--- a/src/libs/musl.zig
+++ b/src/libs/musl.zig
@@ -831,8 +831,6 @@ const src_files = [_][]const u8{
     "musl/src/math/__expo2f.c",
     "musl/src/math/fdimf.c",
     "musl/src/math/fdiml.c",
-    "musl/src/math/finite.c",
-    "musl/src/math/finitef.c",
     "musl/src/math/fma.c",
     "musl/src/math/fmaf.c",
     "musl/src/math/fmal.c",
diff --git a/src/libs/wasi_libc.zig b/src/libs/wasi_libc.zig
index 75840076a50064095e72ae64cdb46013ed756a5e..fbc5f5a142d7dcec086d2333446a3ea85bd8b17b 100644
--- a/src/libs/wasi_libc.zig
+++ b/src/libs/wasi_libc.zig
@@ -697,8 +697,6 @@ const libc_top_half_src_files = [_][]const u8{
     "musl/src/math/expm1l.c",
     "musl/src/math/fdimf.c",
     "musl/src/math/fdiml.c",
-    "musl/src/math/finite.c",
-    "musl/src/math/finitef.c",
     "musl/src/math/fma.c",
     "musl/src/math/fmaf.c",
     "musl/src/math/ilogb.c",
-- 
2.54.0