diff --git a/src/library/grDevices/src/chull.c b/src/library/grDevices/src/chull.c
index 77ffe87b36..aebcfb8ccc 100644
--- a/src/library/grDevices/src/chull.c
+++ b/src/library/grDevices/src/chull.c
@@ -433,7 +433,6 @@ SEXP chull(SEXP x)
     for (int i = 0; i < n; i++) in[i] = i+1;
     int *ih = (int*)R_alloc(4*n, sizeof(int));
     x = PROTECT(coerceVector(x, REALSXP));
-    if(TYPEOF(x) != REALSXP) error("'x' is not numeric");
     in_chull(&n, REAL(x), &n, in, ih+n, ih+2*n, ih, &nh, ih+3*n);
     SEXP ans = allocVector(INTSXP, nh);
     int *ians = INTEGER(ans);
diff --git a/src/library/graphics/src/base.c b/src/library/graphics/src/base.c
index 1e6dfcbe7d..d3348c1c92 100644
--- a/src/library/graphics/src/base.c
+++ b/src/library/graphics/src/base.c
@@ -351,7 +351,7 @@ static SEXP baseCallback(GEevent task, pGEDevDesc dd, SEXP data)
 	    /* Modify the saved settings so this effects display list too */
 	    ddpSaved->scale *= rf;
 	} else
-	  error("event 'GE_ScalePS' requires a single numeric value");
+	  error("event 'GE_ScalePS' requires a single numeric (double) value");
 	break;
     }
     }
diff --git a/src/library/stats/src/port.c b/src/library/stats/src/port.c
index 331ede0122..006cbceba9 100644
--- a/src/library/stats/src/port.c
+++ b/src/library/stats/src/port.c
@@ -1,6 +1,6 @@
 /*
  *  R : A Computer Language for Statistical Data Analysis
- *  Copyright (C) 2005-2024   The R Core Team.
+ *  Copyright (C) 2005-2025   The R Core Team.
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -382,16 +382,15 @@ SEXP port_nlminb(SEXP fn, SEXP gr, SEXP hs, SEXP rho,
     if (isNull(rho)) {
 	error(_("use of NULL environment is defunct"));
 	rho = R_BaseEnv;
-    } else
-    if (!isEnvironment(rho))
+    } else if (!isEnvironment(rho))
 	error(_("'rho' must be an environment"));
     if (!isReal(d) || n < 1)
-	error(_("'d' must be a nonempty numeric vector"));
+	error(_("'d' must be a nonempty numeric (double) vector"));
     if (hs != R_NilValue && gr == R_NilValue)
 	error(_("When Hessian defined must also have gradient defined"));
     if (R_NilValue == (xpt = findVarInFrame(rho, dot_par_symbol)) ||
 	!isReal(xpt) || LENGTH(xpt) != n)
-	error(_("environment 'rho' must contain a numeric vector '.par' of length %d"),
+	error(_("environment 'rho' must contain a numeric (double) vector '.par' of length %d"),
 	      n);
     /* We are going to alter .par, so must duplicate it */
     defineVar(dot_par_symbol, duplicate(xpt), rho);
@@ -405,7 +404,7 @@ SEXP port_nlminb(SEXP fn, SEXP gr, SEXP hs, SEXP rho,
 		b[2*i] = rl[i];
 		b[2*i + 1] = ru[i];
 	    }
-	} else error(_("'lower' and 'upper' must be numeric vectors"));
+	} else error(_("'lower' and 'upper' must be numeric (double) vectors"));
     }
     if (gr != R_NilValue) {
 	g = (double *)R_alloc(n, sizeof(double));
@@ -552,7 +551,7 @@ SEXP port_nlsb(SEXP m, SEXP d, SEXP gg, SEXP iv, SEXP v,
 	*rd = (double *)R_alloc(nd, sizeof(double));
 
     if (!isReal(d) || n < 1)
-	error(_("'d' must be a nonempty numeric vector"));
+	error(_("'d' must be a nonempty numeric (double) vector"));
     if(!isNewList(m)) error(_("m must be a list"));
 				/* Initialize parameter vector */
     getPars = PROTECT(lang1(getFunc(m, "getPars", "m")));
diff --git a/src/main/raw.c b/src/main/raw.c
index 67892caaef..cdb7b97bb5 100644
--- a/src/main/raw.c
+++ b/src/main/raw.c
@@ -151,8 +151,6 @@ attribute_hidden SEXP do_numToInts(SEXP call, SEXP op, SEXP args, SEXP env)
 {
     checkArity(op, args);
     SEXP x = PROTECT(coerceVector(CAR(args), REALSXP));
-    if (!isReal(x))
-	error(_("argument 'x' must be a numeric vector"));
     SEXP ans = PROTECT(allocVector(INTSXP, 2*XLENGTH(x)));
     R_xlen_t i, j = 0;
     double *x_ = REAL(x);
@@ -169,13 +167,11 @@ attribute_hidden SEXP do_numToInts(SEXP call, SEXP op, SEXP args, SEXP env)
     UNPROTECT(2);
     return ans;
 }
-// split "real", i.e. = double = 64-bitd, to bits (<==> do_intToBits( do_numToInts(..) .. ))
+// split "real", i.e. = double = 64-bit, to bits (<==> do_intToBits( do_numToInts(..) .. ))
 attribute_hidden SEXP do_numToBits(SEXP call, SEXP op, SEXP args, SEXP env)
 {
     checkArity(op, args);
     SEXP x = PROTECT(coerceVector(CAR(args), REALSXP));
-    if (!isReal(x))
-	error(_("argument 'x' must be a numeric vector"));
     SEXP ans = PROTECT(allocVector(RAWSXP, 64*XLENGTH(x)));
     R_xlen_t i, j = 0;
     double *x_ = REAL(x);