Update README.md

Author: cpp-tutor

README.md

@@ -10,19 +10,20 @@ The "scripts" subdirectory contains a C++ program which extracts all programs fr
 
 ## Compiling under Windows
 
-All programs compile successfully under Windows with Visual Studio 2022 (v17.x or later).
+Most programs compile successfully under Windows with Visual Studio 2022 (v17.5 or later), some of the modules versions do not currently compile.
 
-The supplied batch scripts `build-vs2022-headers.bat` and
-`build-vs2022-modules.bat` can be used to compile all of the programs within a Visual Studio command prompt, simply run:
+The supplied batch scripts `build-vs2022-headers.bat` and `build-vs2022-modules.bat` can be used to compile all of the programs within a Visual Studio command prompt, simply run:
 
-```C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars64.bat```
+```
+C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars64.bat
+```
 
 or similar in a command window, or create a desktop link, and then run either of the build scripts.
 
 Alternatively, to compile individual programs from within a Visual Studio command prompt run either (modules):
 
 ```
-cl /EHsc /std:c++latest /experimental:moodule /MD 00-example.cpp
+cl /EHsc /std:c++latest /MTd 00-example.cpp
 ```
 
 or (headers):
@@ -31,7 +32,7 @@ or (headers):
 cl /EHsc /std:c++latest 00-example.cpp
 ```
 
-substituting the correct file for `00-example.cpp` in either case.
+substituting the correct file for `00-example.cpp` in either case. Note that the modules versions need file `std.obj` in the current directory, see the build script for how to create this.
 
 ## Compiling under Linux
 
@@ -49,4 +50,4 @@ clang++ -std=c++20 -o 00-example 00-example.cpp
 
 substituting both occurrencies of `00-example` with the correct file name.
 
-Alternatively, run one of the supplied shell scripts `build-gcc-headers.sh` or `build-clang-headers.sh` which are supplied in the "headers" subdirectory, or `build-clang-modules.sh` found in the "modules" subdirectory. (The last of these needs to change `import std.core;` to `import std;` for each source file before compilation, using the `sed` utility.)
+Alternatively, run one of the supplied shell scripts `build-gcc-headers.sh` or `build-clang-headers.sh` which are supplied in the "headers/build" subdirectory, or `build-clang-modules.sh` found in the "modules/build" subdirectory.