diff -rauN firefox-111.0.1/modules/fdlibm/src/math_private.h firefox-111.0.1-fdlibm-patch/modules/fdlibm/src/math_private.h
--- firefox-111.0.1/modules/fdlibm/src/math_private.h	2023-03-21 14:16:09.000000000 +0100
+++ firefox-111.0.1-fdlibm-patch/modules/fdlibm/src/math_private.h	2023-04-08 16:50:07.828564320 +0200
@@ -30,9 +30,17 @@
  * Adapted from https://github.com/freebsd/freebsd-src/search?q=__double_t
  */
 
+#if defined __FLT_EVAL_METHOD__ && (__FLT_EVAL_METHOD__ == 2)
+typedef long double  __double_t;
+#else
 typedef double      __double_t;
+#endif
 typedef __double_t  double_t;
+#if defined __FLT_EVAL_METHOD__ && (__FLT_EVAL_METHOD__ == 2)
+typedef long double __float_t;
+#else
 typedef float       __float_t;
+#endif
 
 /*
  * The original fdlibm code used statements like:
