diff --git a/src/library/base/R/as.R b/src/library/base/R/as.R
index ee7b6632cfa..813694d5416 100644
--- a/src/library/base/R/as.R
+++ b/src/library/base/R/as.R
@@ -20,7 +20,7 @@ as.single <- function(x,...) UseMethod("as.single")
 as.single.default <- function(x,...)
     structure(.Internal(as.vector(x,"double")), Csingle=TRUE)
 
-# as.character is now internal.  The default method remains here to
+# as.character is now .Primitive().  The default method remains here to
 # preserve the semantics that for a call with an object argument
 # dispatching is done first on as.character and then on as.vector.
 as.character.default <- function(x,...) .Internal(as.vector(x, "character"))
diff --git a/src/library/base/R/attr.R b/src/library/base/R/attr.R
index a82aa3e3fae..968e4888514 100644
--- a/src/library/base/R/attr.R
+++ b/src/library/base/R/attr.R
@@ -33,7 +33,7 @@
         ## Be careful to set dim before dimnames.
 	if(h.dim && L == prod(d1)) attr(x, "dim") <- dm <- d1
 	if(h.dmn && !is.null(dm)) {
-            ddn <- vapply(dn1, length, 1, USE.NAMES=FALSE)
+            ddn <- lengths(dn1, use.names=FALSE)
             if( all((dm == ddn)[ddn > 0]) ) attr(x, "dimnames") <- dn1
         }
         ## don't set if it has 'dim' now
diff --git a/src/library/base/R/load.R b/src/library/base/R/load.R
index 31f2e03bd56..cd2f41fa515 100644
--- a/src/library/base/R/load.R
+++ b/src/library/base/R/load.R
@@ -90,7 +90,8 @@ save <- function(..., list = character(),
             }
         }
         if (is.character(file)) {
-	    if(!nzchar(file)) stop("'file' must be non-empty string")
+	    if(!nzchar(file)) 
+                stop(gettextf("'%s' must be a non-empty string", "file"), domain = NA)
 	    if(!is.character(compress)) {
 		if(!is.logical(compress))
 		    stop("'compress' must be logical or character")
@@ -128,9 +129,8 @@ save <- function(..., list = character(),
 save.image <- function (file = ".RData", version = NULL, ascii = FALSE,
                         compress = !ascii, safe = TRUE)
 {
-    if (! is.character(file) || file == "")
-        stop("'file' must be non-empty string")
-
+    if (!is.character(file) || length(file) != 1 || file == "")
+        stop(gettextf("'%s' must be a non-empty string", "file"), domain = NA)
     opts <- getOption("save.image.defaults")
     if(is.null(opts)) opts <- getOption("save.defaults")
 
diff --git a/src/library/base/R/methodsSupport.R b/src/library/base/R/methodsSupport.R
index 5a0fa591ab6..42c916f2d32 100644
--- a/src/library/base/R/methodsSupport.R
+++ b/src/library/base/R/methodsSupport.R
@@ -34,6 +34,7 @@ trace <- function(what, tracer, exit, at, print, signature,
     ## the correct namespace (e.g., correct version of class())
     call <- sys.call()
     call[[1L]] <- quote(methods:::.TraceWithMethods)
+					# -> ../../methods/R/trace.R
     call$where <- where
     eval.parent(call)
 }
diff --git a/src/library/base/R/serialize.R b/src/library/base/R/serialize.R
index 544ab005c7d..8446fe49f2b 100644
--- a/src/library/base/R/serialize.R
+++ b/src/library/base/R/serialize.R
@@ -1,7 +1,7 @@
 #  File src/library/base/R/serialize.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2019 The R Core Team
+#  Copyright (C) 1995-2023 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
@@ -21,7 +21,8 @@ saveRDS <-
              compress = TRUE, refhook = NULL)
 {
     if(is.character(file)) {
-	if(file == "") stop("'file' must be non-empty string")
+        if(length(file) != 1 || file == "")
+            stop(gettextf("'%s' must be a non-empty string", "file"), domain = NA)
 	object <- object # do not create corrupt file if object does not exist
 	mode <- if(ascii %in% FALSE) "wb" else "w"
 	con <- if (is.logical(compress))
diff --git a/src/library/base/R/sort.R b/src/library/base/R/sort.R
index 52f22fd8478..3d654241a79 100644
--- a/src/library/base/R/sort.R
+++ b/src/library/base/R/sort.R
@@ -16,6 +16,7 @@
 #  A copy of the GNU General Public License is available at
 #  https://www.R-project.org/Licenses/
 
+## interfacing to ALTREP meta data about "sorted"ness and presence of NAs:
 .doSortWrap <- local({
     ## this matches the enum in Rinternals.h
     INCR_NA_1ST <-  2
@@ -52,7 +53,7 @@
     }
 })
 ## temporary, for sort.int and sort.list captured as S4 default methods
-## .doWrap introduced in r74405 | 2018-03-14   replaced by .doSoftWrap in r74504 | 2018-04-02
+## .doWrap introduced in r74405 | 2018-03-14   replaced by .doSortWrap in r74504 | 2018-04-02
 .doWrap <- .doSortWrap
 
 sort <- function(x, decreasing = FALSE, ...)
@@ -81,7 +82,7 @@ sort.int <-
              method = c("auto", "shell", "quick", "radix"),
              index.return = FALSE)
 {
-    ## fastpass
+    ## fastpass {for "known to be sorted" x (ALTREP meta data; see .doSortWrap()}
     decreasing <- as.logical(decreasing)
     if (is.null(partial) && !index.return && is.numeric(x)) {
         if (.Internal(sorted_fpass(x, decreasing, na.last))) {
@@ -180,10 +181,10 @@ sort.int <-
     if (isfact)
         y <- (if (isord) ordered else factor)(y, levels = seq_len(nlev),
             labels = lev)
-    if (is.null(partial)) {
-        y <- .doSortWrap(y, decreasing, na.last)
-    }
-    y
+    if (is.null(partial))
+        .doSortWrap(y, decreasing, na.last)
+    else
+        y
 }
 
 order <- function(..., na.last = TRUE, decreasing = FALSE,
@@ -191,7 +192,7 @@ order <- function(..., na.last = TRUE, decreasing = FALSE,
 {
     z <- list(...)
 
-    ## fastpass, take advantage of ALTREP metadata
+    ## fastpass, take advantage of ALTREP metadata, see .doSortWrap()
     decreasing <- as.logical(decreasing)
     if (length(z) == 1L && is.numeric(x <- z[[1L]]) && !is.object(x) && length(x) > 0) {
         if (.Internal(sorted_fpass(x, decreasing, na.last)))
diff --git a/src/library/base/R/version.R b/src/library/base/R/version.R
index 01cee76e1fb..79b0482583a 100644
--- a/src/library/base/R/version.R
+++ b/src/library/base/R/version.R
@@ -171,7 +171,7 @@ function(x)
     classes <- class(x)
     nms <- names(x)
     x <- unclass(x)
-    lens <- vapply(x, length, 0L)
+    lens <- lengths(x)
     y <- lapply(x, function(e) sprintf("%o", e))
     ## Maximal number of octal digits needed.
     width <- max(nchar(unlist(y)), 0L)
@@ -382,7 +382,7 @@ function(x, recursive = FALSE)
 {
     ## <NOTE>
     ## Assuming *valid* numeric_version objects, we could simply do:
-    ##   any(vapply(unclass(x), length, 0L) == 0L)
+    ##   any(lengths(unclass(x)) == 0L)
     ## </NOTE>
     anyNA(.encode_numeric_version(x))
 }
diff --git a/src/library/base/man/stopifnot.Rd b/src/library/base/man/stopifnot.Rd
index ec432e8d3c3..1175f4ad9f0 100644
--- a/src/library/base/man/stopifnot.Rd
+++ b/src/library/base/man/stopifnot.Rd
@@ -136,6 +136,18 @@ stopifnot("m must be symmetric"= m == t(m))
 #=> Error: m must be symmetric
 
 options(op)  # revert to previous error handler
+
+##' warnifnot(): a "only-warning" version of stopifnot()
+##'   {Yes, learn how to use do.call(substitute, ...) in a powerful manner !!}
+warnifnot <- stopifnot ; N <- length(bdy <- body(warnifnot))
+bdy        <- do.call(substitute, list(bdy,   list(stopifnot = quote(warnifnot))))
+bdy[[N-1]] <- do.call(substitute, list(bdy[[N-1]], list(stop = quote(warning))))
+body(warnifnot) <- bdy
+warnifnot(1 == 1, 1 < 2, 2 < 2) # => warns " 2 < 2 is not TRUE  "
+warnifnot(exprs = {
+    1 == 1
+    3 < 3  # => warns "3 < 3 is not TRUE"
+})
 }
 \keyword{environment}
 \keyword{programming}
diff --git a/src/library/base/man/table.Rd b/src/library/base/man/table.Rd
index 604f832a548..15dd5c7e3ad 100644
--- a/src/library/base/man/table.Rd
+++ b/src/library/base/man/table.Rd
@@ -150,6 +150,7 @@ with(airquality, table(cut(Temp, quantile(Temp)), Month))
 
 a <- letters[1:3]
 table(a, sample(a))                    # dnn is c("a", "")
+table(a, sample(a), dnn = NULL)        # dimnames() have no names
 table(a, sample(a), deparse.level = 0) # dnn is c("", "")
 table(a, sample(a), deparse.level = 2) # dnn is c("a", "sample(a)")
 
diff --git a/src/library/grDevices/R/postscript.R b/src/library/grDevices/R/postscript.R
index 52e5221d887..0b11f60557e 100644
--- a/src/library/grDevices/R/postscript.R
+++ b/src/library/grDevices/R/postscript.R
@@ -1,7 +1,7 @@
 #  File src/library/grDevices/R/postscript.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2019 The R Core Team
+#  Copyright (C) 1995-2022 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
@@ -961,7 +961,8 @@ embedFonts <- function(file, # The ps or pdf file to convert
                        )
 {
     if(!is.character(file) || length(file) != 1L || !nzchar(file))
-        stop("'file' must be a non-empty character string")
+        stop(gettextf("'%s' must be a non-empty character string", "file"),
+             domain = NA)
     gsexe <- tools::find_gs_cmd()
     if(!nzchar(gsexe)) stop("GhostScript was not found")
     if(.Platform$OS.type == "windows") gsexe <- shortPathName(gsexe)
diff --git a/src/library/methods/src/methods_list_dispatch.c b/src/library/methods/src/methods_list_dispatch.c
index c7df2834c45..cb4e48a334d 100644
--- a/src/library/methods/src/methods_list_dispatch.c
+++ b/src/library/methods/src/methods_list_dispatch.c
@@ -499,11 +499,9 @@ SEXP R_getGeneric(SEXP name, SEXP mustFind, SEXP env, SEXP package)
     value = get_generic(name, env, package);
     if(value == R_UnboundValue) {
 	if(asLogical(mustFind)) {
-	    if(env == R_GlobalEnv)
-		error(_("no generic function definition found for '%s'"),
-		  CHAR(asChar(name)));
-	    else
-		error(_("no generic function definition found for '%s' in the supplied environment"),
+	    error((env == R_GlobalEnv)
+		  ? _("no generic function definition found for '%s'")
+		  : _("no generic function definition found for '%s' in the supplied environment"),
 		  CHAR(asChar(name)));
 	}
 	value = R_NilValue;
diff --git a/src/library/stats/loess-README b/src/library/stats/loess-README
index efe66becc00..c6e4254db00 100644
--- a/src/library/stats/loess-README
+++ b/src/library/stats/loess-README
@@ -1,6 +1,6 @@
 A first try at de-obfuscate the structure, mainly in ./loessf.f :
 
-  ehg182(): warning(message) generator, defined in ./loessc.c
+  loesswarn(), formerly ehg182() : warning(message) generator, defined in ./loessc.c
 	    called from almost any non-trivial function in loessf.f
 	    and hence *NOT* in the following calling structure
 
diff --git a/src/library/stats/man/Hypergeometric.Rd b/src/library/stats/man/Hypergeometric.Rd
index c8fe62e4565..7ad2101181d 100644
--- a/src/library/stats/man/Hypergeometric.Rd
+++ b/src/library/stats/man/Hypergeometric.Rd
@@ -1,6 +1,6 @@
 % File src/library/stats/man/Hypergeometric.Rd
 % Part of the R package, https://www.R-project.org
-% Copyright 1995-2020 R Core Team
+% Copyright 1995-2023 R Core Team
 % Distributed under GPL 2 or later
 
 \name{Hypergeometric}
@@ -111,7 +111,9 @@ m <- 10; n <- 7; k <- 8
 x <- 0:(k+1)
 rbind(phyper(x, m, n, k), dhyper(x, m, n, k))
 all(phyper(x, m, n, k) == cumsum(dhyper(x, m, n, k)))  # FALSE
-\donttest{## but error is very small:
+\donttest{## but errors are very small:
 signif(phyper(x, m, n, k) - cumsum(dhyper(x, m, n, k)), digits = 3)
-}}
+}
+stopifnot(abs(phyper(x, m, n, k) - cumsum(dhyper(x, m, n, k))) < 5e-16)
+}
 \keyword{distribution}
diff --git a/src/library/stats/man/loess.Rd b/src/library/stats/man/loess.Rd
index 39294a0d9a2..8352d45210a 100644
--- a/src/library/stats/man/loess.Rd
+++ b/src/library/stats/man/loess.Rd
@@ -1,6 +1,6 @@
 % File src/library/stats/man/loess.Rd
 % Part of the R package, https://www.R-project.org
-% Copyright 1995-2015 R Core Team
+% Copyright 1995-2023 R Core Team
 % Distributed under GPL 2 or later
 
 \name{loess}
@@ -57,7 +57,7 @@ loess(formula, data, weights, subset, na.action, model = FALSE,
     (\emph{if} \code{control} is not specified).}
 }
 \description{
-  Fit a polynomial surface determined by one or more numerical
+  Fit a locally polynomial surface determined by one or more numerical
   predictors, using local fitting.
 }
 \details{
@@ -83,7 +83,9 @@ loess(formula, data, weights, subset, na.action, model = FALSE,
   speed.  See \code{\link{loess.control}} for details.
 }
 \value{
-  An object of class \code{"loess"}.% otherwise entirely unspecified (!)
+  An object of class \code{"loess"}, % otherwise entirely unspecified (!)
+  with \code{print()}, \code{\link{summary}()}, \code{\link{predict}} and
+  \code{\link{anova}} methods.
 }
 \references{
   W. S. Cleveland, E. Grosse and W. M. Shyu (1992) Local regression
@@ -124,8 +126,8 @@ cars.lo <- loess(dist ~ speed, cars)
 predict(cars.lo, data.frame(speed = seq(5, 30, 1)), se = TRUE)
 # to allow extrapolation
 cars.lo2 <- loess(dist ~ speed, cars,
-  control = loess.control(surface = "direct"))
+                  control = loess.control(surface = "direct"))
 predict(cars.lo2, data.frame(speed = seq(5, 30, 1)), se = TRUE)
-}
+}%% Add a 2D example, e.g. like 'topo' of MASS ch04.R, but using volcano?
 \keyword{smooth}
 \keyword{loess}
diff --git a/src/library/stats/src/deriv.c b/src/library/stats/src/deriv.c
index 0fc1c011b6e..4291fecbb4d 100644
--- a/src/library/stats/src/deriv.c
+++ b/src/library/stats/src/deriv.c
@@ -781,13 +781,13 @@ static SEXP AddParens(SEXP expr)
 
 SEXP doD(SEXP args)
 {
-    SEXP expr, var;
     args = CDR(args);
+    SEXP expr;
     if (isExpression(CAR(args))) expr = VECTOR_ELT(CAR(args), 0);
     else expr = CAR(args);
     if (!(isLanguage(expr) || isSymbol(expr) || isNumeric(expr) || isComplex(expr)))
         error(_("expression must not be type '%s'"), type2char(TYPEOF(expr)));
-    var = CADR(args);
+    SEXP var = CADR(args);
     if (!isString(var) || length(var) < 1)
 	error(_("variable must be a character string"));
     if (length(var) > 1)
diff --git a/src/library/stats/src/massdist.c b/src/library/stats/src/massdist.c
index 12216e711dc..fb69a3a8412 100644
--- a/src/library/stats/src/massdist.c
+++ b/src/library/stats/src/massdist.c
@@ -3,8 +3,7 @@
  *  Copyright (C) 1996-2020	The R Core Team
  *  Copyright (C) 2005		The R Foundation
 
- *  "HACKED" to allow weights by Adrian Baddeley
- *  Changes indicated by 'AB'
+ *  "HACKED" to allow weights by Adrian Baddeley (commit r34130, 2005-04-30)
  * -------
  *  FIXME   Does he want 'COPYRIGHT' ?
  * -------
@@ -34,7 +33,7 @@
 /* NB: this only works on the lower half of y, but pads with zeros. */
 SEXP BinDist(SEXP sx, SEXP sw, SEXP slo, SEXP shi, SEXP sn)
 {
-    PROTECT(sx = coerceVector(sx, REALSXP)); 
+    PROTECT(sx = coerceVector(sx, REALSXP));
     PROTECT(sw = coerceVector(sw, REALSXP));
     int n = asInteger(sn);
     if (n == NA_INTEGER || n <= 0) error("invalid '%s' argument", "n");
diff --git a/src/library/tools/R/Rd2latex.R b/src/library/tools/R/Rd2latex.R
index 28d6b29963a..08be6e054ee 100644
--- a/src/library/tools/R/Rd2latex.R
+++ b/src/library/tools/R/Rd2latex.R
@@ -82,10 +82,7 @@ Rd2latex <- function(Rd, out = "", defines = .Platform$OS.type,
             }
     }
 
-    if (concordance)
-    	conc <- activeConcordance()
-    else
-    	conc <- NULL
+    conc <- if(concordance) activeConcordance() # else NULL
     
     last_char <- ""
     of0 <- function(...) of1(paste0(...))
diff --git a/src/library/tools/R/testing.R b/src/library/tools/R/testing.R
index ff98e3e9f09..ccc573d1456 100644
--- a/src/library/tools/R/testing.R
+++ b/src/library/tools/R/testing.R
@@ -833,8 +833,10 @@ testInstalledBasic <- function(scope = c("basic", "devel", "both", "internet", "
         runone("datetime5")
         message("running tests of consistency of as/is.*", domain = NA)
         runone("isas-tests")
-        message("running tests of random deviate generation -- fails occasionally")
+        message("running tests of random deviate generation (should no longer ever fail)")
         runone("p-r-random-tests", TRUE)
+        message("running miscellanous strict devel checks", domain = NA)
+        if (runone("misc-devel")) return(invisible(1L))
         message("running tests demos from base and stats", domain = NA)
         if (runone("demos")) return(invisible(1L))
         if (runone("demos2")) return(invisible(1L))
diff --git a/src/library/utils/R/debugcall.R b/src/library/utils/R/debugcall.R
index 06e12b7878d..f4ca9cbaa37 100644
--- a/src/library/utils/R/debugcall.R
+++ b/src/library/utils/R/debugcall.R
@@ -1,7 +1,7 @@
 ##  File src/library/utils/R/debugcall.R
 ##  Part of the R package, https://www.R-project.org
 ##
-##  Copyright (C) 1995-2016 The R Core Team
+##  Copyright (C) 1995-2023 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
@@ -19,26 +19,25 @@
 .debugcall <- function(call, op) {
     funsym <- deparse(call[[1L]])
     func <- get(funsym, parent.frame(2L), mode="function")
-    
+
     have.methods <- isNamespaceLoaded("methods")
     func <- if(is.primitive(func)) {
-        if (have.methods) methods::getGeneric(func)
-    } else func
+                if (have.methods) methods::getGeneric(func)
+            } else func
     if(is.null(func)) {
         stop("Cannot debug primitive functions unless they are implicit generics (requires loading the methods package)")
     }
     mcall <- match.call(func, call)
 
     env <- parent.frame(2L)
-    sig <- NULL
-    s4Generic <- have.methods && methods::isGeneric(funsym)
-    if(!s4Generic) {
+    if(!(have.methods && methods::isGeneric(funsym))) { # not S4-generic
         s3ret <- isS3stdGeneric(func)
         if(s3ret) {
             genname <- names(s3ret)
-            arg <- eval(mcall[[2L]], envir=env) 
+            arg <- eval(mcall[[2L]], envir=env)
             func <- getS3method(genname, class(arg))
         }
+        sig <- NULL
     } else {
         sig <- .signatureFromCall(func, mcall, env)
     }
@@ -49,7 +48,7 @@
     args <- formals(fdef)
     call <- match.call(fdef, expr, expand.dots = FALSE)
     args[names(call[-1L])] <- call[-1L]
-    if ("..." %in% names(call)) 
+    if ("..." %in% names(call))
         args$... <- args$...[[1L]]
     sigNames <- fdef@signature
     sigClasses <- rep.int("missing", length(sigNames))
@@ -68,8 +67,8 @@
             ## the evaluator.
             if (doEval || !simple) {
                 argVal <- try(eval(argExpr, envir))
-                if (methods::is(argVal, "try-error")) 
-                    stop(gettextf("error in trying to evaluate the expression for argument %s (%s)", 
+                if (methods::is(argVal, "try-error"))
+                    stop(gettextf("error in trying to evaluate the expression for argument %s (%s)",
                                   sQuote(arg), deparse(argExpr)), domain = NA)
                 sigClasses[[arg]] <- class(argVal)[1L]
             }
diff --git a/src/library/utils/R/help.search.R b/src/library/utils/R/help.search.R
index ae4509ce780..4b61b4d2339 100644
--- a/src/library/utils/R/help.search.R
+++ b/src/library/utils/R/help.search.R
@@ -1,7 +1,7 @@
 #  File src/library/utils/R/help.search.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2018 The R Core Team
+#  Copyright (C) 1995-2022 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
@@ -122,7 +122,7 @@ function(pattern, fields = c("alias", "concept", "title"),
 {
     ### Argument handling.
     .wrong_args <- function(args)
-	gettextf("argument %s must be a single character string", sQuote(args))
+	gettextf("argument %s must be a character string", sQuote(args))
     if(is.logical(verbose)) verbose <- 2 * as.integer(verbose)
     fuzzy <- agrep
     if(!missing(pattern)) {
diff --git a/src/library/utils/R/help.start.R b/src/library/utils/R/help.start.R
index 77253e0721f..081acc8a6b1 100644
--- a/src/library/utils/R/help.start.R
+++ b/src/library/utils/R/help.start.R
@@ -1,7 +1,7 @@
 #  File src/library/utils/R/help.start.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2019 The R Core Team
+#  Copyright (C) 1995-2022 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
@@ -55,14 +55,16 @@ browseURL <- function(url, browser = getOption("browser"), encodeIfNeeded=FALSE)
     WINDOWS <- .Platform$OS.type == "windows"
 
     if (!is.character(url) || length(url) != 1L|| !nzchar(url))
-        stop("'url' must be a non-empty character string")
+        stop(gettextf("'%s' must be a non-empty character string", "url"),
+             domain = NA)
     if(identical(browser, "false")) return(invisible())
     if(WINDOWS && is.null(browser)) return(shell.exec(url))
     if (is.function(browser))
         return(invisible(browser(if(encodeIfNeeded) URLencode(url) else url)))
 
     if (!is.character(browser) || length(browser) != 1L || !nzchar(browser))
-        stop("'browser' must be a non-empty character string")
+        stop(gettextf("'%s' must be a non-empty character string", "browser"),
+             domain = NA)
     if (WINDOWS) {
         ## No shell used, but spaces are possible
         return(system(paste0('"', browser, '" ',
diff --git a/src/library/utils/R/packages2.R b/src/library/utils/R/packages2.R
index 74abd8f4145..890a89bdacc 100644
--- a/src/library/utils/R/packages2.R
+++ b/src/library/utils/R/packages2.R
@@ -168,8 +168,8 @@ install.packages <-
              keep_outputs = FALSE,
              ...)
 {
-    if (!is.character(type))
-        stop("invalid 'type'; must be a character string")
+    if(!(is.character(type) && length(type) == 1L))
+        stop(gettextf("'%s' must be a character string", "type"), domain = NA)
     type2 <- .Platform$pkgType
     if (type == "binary") {
         if (type2 == "source")
diff --git a/src/library/utils/R/sessionInfo.R b/src/library/utils/R/sessionInfo.R
index 52813c3abaf..7f990873c22 100644
--- a/src/library/utils/R/sessionInfo.R
+++ b/src/library/utils/R/sessionInfo.R
@@ -135,7 +135,7 @@ sessionInfo <- function(package = NULL)
     }
     z$matprod <- as.character(options("matprod"))
     es <- extSoftVersion()
-    z$BLAS <- as.character(es["BLAS"]) #drop name
+    z$BLAS <- es[["BLAS"]] #drop name
     z$LAPACK <- La_library()
     z$LA_version <- La_version()
     l10n <- l10n_info()
diff --git a/src/library/utils/R/zip.R b/src/library/utils/R/zip.R
index d73534a6a10..b667975266d 100644
--- a/src/library/utils/R/zip.R
+++ b/src/library/utils/R/zip.R
@@ -1,7 +1,7 @@
 #  File src/library/utils/R/zip.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2020 The R Core Team
+#  Copyright (C) 1995-2023 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
@@ -34,8 +34,8 @@ unzip <-
     } else {
         WINDOWS <- .Platform$OS.type == "windows"
         if(!is.character(unzip) || length(unzip) != 1L || !nzchar(unzip))
-            stop("'unzip' must be a single character string")
-        zipfile <- path.expand(zipfile)
+            stop(gettextf("'%s' must be a non-empty character string", "unzip"),
+                 domain = NA)
         if (list) {
             ## -q to suppress per-file and per-archive comments (since 5.52)
             ## it also suppresses the first line "Archive: filename"
@@ -103,8 +103,8 @@ zip <- function(zipfile, files, flags = "-r9X", extras = "",
     if (missing(flags) && (!is.character(files) || !length(files)))
         stop("'files' must be a character vector specifying one or more filepaths")
     if(!is.character(zip) || length(zip) != 1L || !nzchar(zip))
-        stop("argument 'zip' must be a non-empty character string")
-
+        stop(gettextf("'%s' must be a non-empty character string", "zip"),
+             domain = NA)
     args <- c(flags, shQuote(path.expand(zipfile)),
               shQuote(files), extras)
     if (sum(nchar(c(args, Sys.getenv()))) + length(args) > 8000) {
diff --git a/src/library/utils/man/SweaveUtils.Rd b/src/library/utils/man/SweaveUtils.Rd
index d05d005c014..a19dfcb4188 100644
--- a/src/library/utils/man/SweaveUtils.Rd
+++ b/src/library/utils/man/SweaveUtils.Rd
@@ -21,8 +21,8 @@
 \description{
   These functions are handy for writing Sweave drivers and are
   considered internal and hence not documented.  Look at the source code
-  of the Sweave Latex driver (in this
-  package) or the HTML driver (in the R2HTML package from CRAN) to see
+  of the Sweave \LaTeX driver (in this
+  package) or the HTML driver (in the \pkg{R2HTML} package from CRAN) to see
   how they can be used.
 }
 \usage{
diff --git a/src/library/utils/man/hashtab.Rd b/src/library/utils/man/hashtab.Rd
index 5abc5ce7564..d6f3a91286b 100644
--- a/src/library/utils/man/hashtab.Rd
+++ b/src/library/utils/man/hashtab.Rd
@@ -1,6 +1,6 @@
 % File src/library/utils/man/hashtab.Rd
 % Part of the R package, https://www.R-project.org
-% Copyright 2009-2021 R Core Team
+% Copyright 2009-2023 R Core Team
 % Distributed under GPL 2 or later
 
 \name{hashtab}
@@ -139,7 +139,9 @@ is.hashtab(x)
 \examples{
 ## Create a new empty hash table.
 h1 <- hashtab()
+## IGNORE_RDIFF_BEGIN
 h1
+## IGNORE_RDIFF_END
 
 ## Add some key/value pairs.
 sethash(h1, NULL, 1)
@@ -175,7 +177,9 @@ identical(h1, h2)
 ## set in one, see in the "other"  <==> really one object with 2 names
 sethash(h2, NULL, 77)
 gethash(h1, NULL)
+## IGNORE_RDIFF_BEGIN
 str(h1)
+## IGNORE_RDIFF_END
 
 ## An example of using  maphash():  get all hashkeys of a hash table:
 hashkeys <- function(h) {
diff --git a/src/library/utils/man/modifyList.Rd b/src/library/utils/man/modifyList.Rd
index 88509c667e9..a9bdce3f002 100644
--- a/src/library/utils/man/modifyList.Rd
+++ b/src/library/utils/man/modifyList.Rd
@@ -16,7 +16,7 @@ modifyList(x, val, keep.null = FALSE)
 \arguments{
   \item{x}{A named \code{\link{list}}, possibly empty.}
   \item{val}{A named list with components to replace corresponding
-    components in \code{x}.}
+    components in \code{x} or add new components.}
   \item{keep.null}{ If \code{TRUE}, \code{NULL} elements in \code{val}
     become \code{NULL} elements in \code{x}.  Otherwise, the
     corresponding element, if present, is deleted from \code{x}. }