merge 9.0

3 files changed, 37 insertions, 26 deletions

diff --git a/README.md b/README.md
index c6ffd6f..44016e8 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,7 @@ site](https://sourceforge.net/projects/tcl/files/Tcl/).
 Tcl provides a powerful platform for creating integration applications that
 tie together diverse applications, protocols, devices, and frameworks.
 When paired with the Tk toolkit, Tcl provides the fastest and most powerful
-way to create GUI applications that run on PCs, Unix, and Mac OS X.
+way to create GUI applications that run on PCs, Unix, and macOS.
 Tcl can also be used for a variety of web-related tasks and for creating
 powerful command languages for applications.
 
diff --git a/generic/tclIOCmd.c b/generic/tclIOCmd.c
index 485812f..bd3a462 100644
--- a/generic/tclIOCmd.c
+++ b/generic/tclIOCmd.c
@@ -948,8 +948,16 @@ Tcl_ExecObjCmd(
 		Tcl_SetResult(interp, "No value given for option -encoding.",
 			TCL_STATIC);
 		return TCL_ERROR;
+	    } else {
+		Tcl_Encoding encoding;
+		encodingObj = objv[skip];
+		/* Verify validity - bug [da5e1bc7bc] */
+		if (Tcl_GetEncodingFromObj(interp, encodingObj, &encoding)
+			!= TCL_OK) {
+		    return TCL_ERROR;
+		}
+		Tcl_FreeEncoding(encoding);
 	    }
-	    encodingObj = objv[skip];
 	    break;
 	}
     }
@@ -1014,16 +1022,14 @@ Tcl_ExecObjCmd(
 
     /* Bug [0f1ddc0df7] - encoding errors - use replace profile */
     if (Tcl_SetChannelOption(interp, chan, "-profile", "replace") != TCL_OK) {
-	return TCL_ERROR;
+	goto errorWithOpenChannel;
     }
 
     /* TIP 716 */
-    if (encodingObj) {
-	if (Tcl_SetChannelOption(
-		interp, chan, "-encoding", Tcl_GetString(encodingObj)) !=
-	    TCL_OK) {
-	    return TCL_ERROR;
-	}
+    if (encodingObj &&
+	Tcl_SetChannelOption(interp, chan, "-encoding", 
+	    Tcl_GetString(encodingObj)) != TCL_OK) {
+	goto errorWithOpenChannel;
     }
 
     TclNewObj(resultPtr);
@@ -1042,7 +1048,7 @@ Tcl_ExecObjCmd(
 			Tcl_PosixError(interp)));
 		Tcl_DecrRefCount(resultPtr);
 	    }
-	    return TCL_ERROR;
+	    goto errorWithOpenChannel;
 	}
     }
 
@@ -1069,6 +1075,11 @@ Tcl_ExecObjCmd(
     Tcl_SetObjResult(interp, resultPtr);
 
     return result;
+
+errorWithOpenChannel:
+    /* Interpreter should already contain error. Pass NULL to not overwrite */
+    (void)Tcl_CloseEx(NULL, chan, 0);
+    return TCL_ERROR;
 }
 
 /*
diff --git a/macosx/README b/macosx/README
index f5e3716..c4221e4 100644
--- a/macosx/README
+++ b/macosx/README
@@ -1,7 +1,7 @@
-Tcl Mac OS X README
+Tcl macOS README
 -------------------
 
-This is the README file for the Mac OS X/Darwin version of Tcl.
+This is the README file for the macOS/Darwin version of Tcl.
 
 
 1. Where to go for support
@@ -63,14 +63,15 @@ framework directories:
 3. Building Tcl on Mac OS X
 ---------------------------
 
-- At least Mac OS X 10.3 is required to build Tcl.
-Apple's Xcode Developer Tools need to be installed (only the most recent version
-matching your OS release is supported), the Xcode installer is available on Mac
-OS X install media or may be present in /Applications/Installers on Macs that
-came with OS X preinstalled. The most recent version can always be downloaded
-from the ADC website http://connect.apple.com (free ADC membership required).
+- Tcl supports macOS 10.13 and newer.
+While Tcl may build on earlier versions of the OS, it is not tested on versions
+older than 10.13.  You will need to install an  Apple clang toolchain either by
+downloading the Xcode app from Apple's App Store, or by installing the Command
+Line Tools. The Command Line Tools can be installed by running the command:
+    xcode-select --install
+in the Terminal.
 
-- Tcl is most easily built as a Mac OS X framework via GNUmakefile in tcl/macosx
+- Tcl is most easily built as a macOS framework via the GNUmakefile in tcl/macosx
 (see below for details), but can also be built with the standard unix configure
 and make buildsystem in tcl/unix as on any other unix platform (indeed, the
 GNUmakefile is just a wrapper around the unix buildsystem).
@@ -78,11 +79,10 @@ The Mac OS X specific configure flags are --enable-framework and
 --disable-corefoundation (which disables CF and notably reverts to the standard
 select based notifier).
 
-- To build universal binaries outside of the Xcode IDE, set CFLAGS as follows:
-	export CFLAGS="-arch x86_64 -arch arm64"
-This requires Mac OS X 10.6 and Xcode 10.2 and will work on any architecture.
-Note that configure requires CFLAGS to contain a least one architecture that can
-be run on the build machine (i.e. x86_64 on Core2/Xeon).
+- To build universal binaries for macOS 10.13 and newer set CFLAGS as follows:
+	export CFLAGS="-arch x86_64 -arch arm64 -mmacosx-version-min=10.13"
+(This will cause clang to set macOS 11 as the target OS for the arm64 architecture
+since Apple Silicon was not supported until macOS 11.)
 Universal builds of Tcl TEA extensions are also possible with CFLAGS set as
 above, they will be [load]able by universal as well as thin binaries of Tcl.
 
@@ -96,8 +96,8 @@ Detailed Instructions for building with macosx/GNUmakefile
 Setup this shell variable as follows:
 	ver="9.0"
 
-- Setup environment variables as desired, e.g. for a universal build on 10.9:
-	CFLAGS="-arch x86_64 -arch arm64 -mmacosx-version-min=10.9"
+- Setup environment variables as desired, for example:
+	CFLAGS="-arch x86_64 -arch arm64 -mmacosx-version-min=10.13"
 	export CFLAGS
 
 - Change to the directory containing the Tcl source tree and build: