--- firefox-91.1.0/modules/fdlibm/src/math_private.h	2021-09-01 19:30:56.000000000 +0200
+++ firefox-91.1.0/modules/fdlibm/src/math_private.h.new	2021-09-08 10:16:59.307089163 +0200
@@ -31,7 +31,6 @@
  */
 
 typedef double      __double_t;
-typedef __double_t  double_t;
 
 /*
  * The original fdlibm code used statements like:
--- firefox-91.1.0/modules/fdlibm/src/e_rem_pio2.cpp	2021-09-01 19:31:24.000000000 +0200
+++ firefox-91.1.0/modules/fdlibm/src/e_rem_pio2.cpp.new	2021-09-08 12:01:14.962844623 +0200
@@ -126,7 +126,7 @@ __ieee754_rem_pio2(double x, double *y)
 	}
 	if(ix<0x413921fb) {	/* |x| ~< 2^20*(pi/2), medium size */
 medium:
-	    fn = rnint((double_t)x*invpio2);
+	    fn = rnint((double)x*invpio2);
 	    n  = irint(fn);
 	    r  = x-fn*pio2_1;
 	    w  = fn*pio2_1t;	/* 1st round good to 85 bit */