bug#28601: 26.0.50; configure: error: Emacs does not support 'x86_64-pc-msys' systems.

[Noam Postavsky]

severity 28601 minor
merge 28601 28888
quit

Trying to consolidate recent bug-gnus-emacs and emacs-devel discussion
about this.

>From f7aa938dbba2514aab73691eb6beea26dfa41d70 Mon Sep 17 00:00:00 2001
From: Noam Postavsky <npostavs@gmail.com>
Date: Tue, 7 Nov 2017 18:01:01 -0500
Subject: [PATCH v3] * nt/INSTALL.W64: Add "Troubleshooting" section
 (Bug#28601).
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Vincent Belaiche <vincent.belaïche@gmail.com>
---
 nt/INSTALL.W64 | 75 ++++++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 57 insertions(+), 18 deletions(-)

diff --git a/nt/INSTALL.W64 b/nt/INSTALL.W64
index 71864ce..c612b13 100644
--- a/nt/INSTALL.W64
+++ b/nt/INSTALL.W64
@@ -35,18 +35,6 @@ Run this file to install MSYS2 in your preferred directory, 
e.g. the default
 C:\msys64 -- this will install MinGW-w64 also.  Note that directory names
 containing spaces may cause problems.
 
-Then you'll need to add the following directories to your Windows PATH
-environment variable:
-
-  c:\msys64\usr\bin;c:\msys64\mingw64\bin
-
-you can do this through Control Panel / System and Security / System /
-Advanced system settings / Environment Variables / Edit path.
-
-Adding these directories to your PATH tells Emacs where to find the DLLs it
-needs to run, and some optional commands like grep and find.  These commands
-will also be available at the Windows console.
-
 ** Download and install the necessary packages
 
 Run c:/msys64/msys2.exe in your MSYS2 directory and you will see a BASH window
@@ -112,11 +100,11 @@ C:\emacs\emacs-24.5:
 ** From the Git repository
 
 To download the Git repository, do something like the following -- this will
-put the Emacs source into C:\emacs\emacs-25:
+put the Emacs source into C:\emacs\emacs-26:
 
   mkdir /c/emacs
   cd /c/emacs
-  git clone git://git.sv.gnu.org/emacs.git emacs-25
+  git clone git://git.sv.gnu.org/emacs.git emacs-26
 
 (We recommend using the command shown on Savannah Emacs project page.)
 
@@ -150,11 +138,10 @@ which 'make install' will use - in this example we set it 
to C:\emacs\emacs-26.
 If a prefix is not specified the files will be put in the standard Unix
 directories located in your C:\msys64 directory, but this is not recommended.
 
-Note also that we need to disable Imagemagick because Emacs does not yet
-support it on Windows.
+Note also that we need to disable Imagemagick and DBUS because Emacs
+does not yet support them on Windows.
 
-  PKG_CONFIG_PATH=/mingw64/lib/pkgconfig \
-  ./configure --prefix=/c/emacs/emacs-26 --without-imagemagick
+  ./configure --prefix=/c/emacs/emacs-26 --without-imagemagick --without-dbus
 
 ** Run make
 
@@ -192,6 +179,14 @@ To test it out, run
 
 and if all went well, you will have a new 64-bit version of Emacs.
 
+When running Emacs from outside the mingw64 shell, you will need to
+add c:\msys64\mingw64\bin to your Windows PATH, or copy the needed
+DLLs into Emacs' bin/ directory.  Otherwise features such as TLS which
+depend on those DLLs will be missing.
+
+You can do this through Control Panel / System and Security / System /
+Advanced system settings / Environment Variables / Edit path.
+
 * Make a shortcut
 
 To make a shortcut to run the new Emacs, right click on the location where you
@@ -202,6 +197,50 @@ You can set any command line options by right clicking on 
the resulting
 shortcut, select Properties, then add any options to the Target command,
 e.g. --debug-init.
 
+* Troubleshooting
+
+** Missing mingw64.exe launcher
+
+Older versions of Msys2 may lack the mingw64.exe launcher program.  If
+you have them, running mingw64_shell.bat or "msys2_shell.cmd -mingw64"
+should work instead.
+
+Alternatively, install mingw64.exe with
+
+    pacman -S msys/msys2-launcher-git
+
+** Check your $PATH
+
+When building Emacs, you should have /mingw64/bin in $PATH, such that running
+
+    which gcc
+
+gives '/mingw64/bin/gcc'.
+
+** Check your $PKG_CONFIG_PATH
+
+It should start with '/mingw64/lib/pkgconfig'.
+
+** Check your MSYS2 fstab file
+
+Assuming that MSYS2 is installed in c:\msys64, make sure that your fstab file
+(c:\msys64\etc\fstab) file contains the following lines (starting a column 0
+in the fstab file):
+
+    c:/msys64/mingw64/bin /mingw64/bin ntfs binary,noacl 0 0
+    c:/msys64/mingw32/bin /mingw32/bin ntfs binary,noacl 0 0
+
+Please note that only the first line is needed for 64bit compilation, the
+second one is for a complete fstab file w.r.t. 32bit compilation.
+
+If there is a space in the diectory where MSYS2 is installed, it shall be
+replaced by \040.  For instance, if MSYS is installed under "C:\Program
+Files\msys64" there must be this line:
+
+    C:/Program\040Files/msys64/mingw64/bin /mingw64/bin ntfs binary,noacl 0 0
+
+As mentioned above, avoiding spaces is preferable.
+
 * Credits
 
 Thanks to Chris Zheng for the original build outline as used by the
-- 
2.6.2.windows.1