diff --git a/lib/msun/src/s_csqrt.c b/lib/msun/src/s_csqrt.c
index cde8792c36f6..ca4924fc2bdc 100644
--- a/lib/msun/src/s_csqrt.c
+++ b/lib/msun/src/s_csqrt.c
@@ -35,16 +35,7 @@ __FBSDID("$FreeBSD$");
 
 #include "math_private.h"
 
-/*
- * gcc doesn't implement complex multiplication or division correctly,
- * so we need to handle infinities specially. We turn on this pragma to
- * notify conforming c99 compilers that the fast-but-incorrect code that
- * gcc generates is acceptable, since the special cases have already been
- * handled.
- */
-#pragma	STDC CX_LIMITED_RANGE	ON
-
-/* We risk spurious overflow for components >= DBL_MAX / (1 + sqrt(2)). */
+/* For avoiding overflow for components >= DBL_MAX / (1 + sqrt(2)). */
 #define	THRESH	0x1.a827999fcef32p+1022
 
 double complex
diff --git a/lib/msun/src/s_csqrtf.c b/lib/msun/src/s_csqrtf.c
index 0f36aa0ffb51..6836a3903c25 100644
--- a/lib/msun/src/s_csqrtf.c
+++ b/lib/msun/src/s_csqrtf.c
@@ -34,20 +34,14 @@ __FBSDID("$FreeBSD$");
 
 #include "math_private.h"
 
-/*
- * gcc doesn't implement complex multiplication or division correctly,
- * so we need to handle infinities specially. We turn on this pragma to
- * notify conforming c99 compilers that the fast-but-incorrect code that
- * gcc generates is acceptable, since the special cases have already been
- * handled.
- */
-#pragma	STDC CX_LIMITED_RANGE	ON
-
 float complex
 csqrtf(float complex z)
 {
-	float a = crealf(z), b = cimagf(z);
 	double t;
+	float a, b;
+
+	a = creal(z);
+	b = cimag(z);
 
 	/* Handle special cases. */
 	if (z == 0)
@@ -82,9 +76,9 @@ csqrtf(float complex z)
 	 */
 	if (a >= 0) {
 		t = sqrt((a + hypot(a, b)) * 0.5);
-		return (CMPLXF(t, b / (2.0 * t)));
+		return (CMPLXF(t, b / (2 * t)));
 	} else {
 		t = sqrt((-a + hypot(a, b)) * 0.5);
-		return (CMPLXF(fabsf(b) / (2.0 * t), copysignf(t, b)));
+		return (CMPLXF(fabsf(b) / (2 * t), copysignf(t, b)));
 	}
 }
diff --git a/lib/msun/src/s_csqrtl.c b/lib/msun/src/s_csqrtl.c
index 8aefbeab1a0b..5ab9406558af 100644
--- a/lib/msun/src/s_csqrtl.c
+++ b/lib/msun/src/s_csqrtl.c
@@ -36,25 +36,18 @@ __FBSDID("$FreeBSD$");
 #include "math_private.h"
 
 /*
- * gcc doesn't implement complex multiplication or division correctly,
- * so we need to handle infinities specially. We turn on this pragma to
- * notify conforming c99 compilers that the fast-but-incorrect code that
- * gcc generates is acceptable, since the special cases have already been
- * handled.
- */
-#pragma	STDC CX_LIMITED_RANGE	ON
-
-/*
- * We risk spurious overflow for components >= LDBL_MAX / (1 + sqrt(2)).
- * Rather than determining the fully precise value at which we might
- * overflow, just use a threshold of approximately LDBL_MAX / 4.
+ * THRESH is now calculated portably (up to 113-bit precision).  However,
+ * the denormal threshold is hard-coded for a 15-bit exponent with the usual
+ * bias.  s_logl.c and e_hypotl have less hard-coding but end up requiring
+ * the same for the exponent and more for the mantissa.
  */
 #if LDBL_MAX_EXP != 0x4000
 #error "Unsupported long double format"
-#else
-#define	THRESH	0x1p16382L
 #endif
 
+/* For avoiding overflow for components >= LDBL_MAX / (1 + sqrt(2)). */
+#define	THRESH	(LDBL_MAX / 2.414213562373095048801688724209698L)
+
 long double complex
 csqrtl(long double complex z)
 {