[nongnu] elpa/pdf-tools 3e35dfa8bc: Add FAQ explaining workaround for M1 Mac compilation problems

[ELPA Syncer]

branch: elpa/pdf-tools
commit 3e35dfa8bc66fc563ad4bcd6a5cd6338969a9fc9
Author: Vedang Manerikar <ved.manerikar@gmail.com>
Commit: Vedang Manerikar <ved.manerikar@gmail.com>

    Add FAQ explaining workaround for M1 Mac compilation problems
    
    In short, the problem is that many people are using Emacs compiled for
    x86_64 on the M1 Mac, which is an ARM64 architecture. There is nothing
    that `pdf-tools` can do here, but the "fix" is straightforward:
    Install Emacs from https://emacsformacosx.com/, which is compiled
    correctly.
    
    Related to: politza/pdf-tools#652, #70
    Closes: #107
---
 README.org | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/README.org b/README.org
index d6bb969671..7d28bb91a9 100644
--- a/README.org
+++ b/README.org
@@ -586,3 +586,44 @@ The idea here is to make the ~server/autobuild~ file the 
single place from which
 This seems like a lot of work, but it is not. If you need a reference, search 
for ~os_gentoo~ or ~os_debian~ in the ~server/autobuild~ file and see how these 
are setup and used. The functions are used to install dependencies on Gentoo 
and Debian respectively, and are simple to copy / change.
 
 When you make your changes, be sure to test them!
+
+** I am on a Macbook M1 and ~pdf-tools~ installation fails with a stack-trace
+:PROPERTIES:
+:CREATED:  [2022-05-09 Mon 20:29]
+:ID:       96D389D8-DD23-4FB0-996C-2D6F70A76BB2
+:END:
+There have been a number of issues around ~pdf-tools~ installation problems on 
M1. ~M-x pdf-tools-install~ throws the following stack trace:
+#+begin_example
+  1 warning generated.
+  ld: warning: ignoring file /opt/homebrew/opt/gettext/lib/libintl.dylib, 
building for macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file 
/opt/homebrew/Cellar/glib/2.72.1/lib/libglib-2.0.dylib, building for 
macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file 
/opt/homebrew/Cellar/poppler/22.02.0/lib/libpoppler-glib.dylib, building for 
macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file 
/opt/homebrew/Cellar/glib/2.72.1/lib/libgobject-2.0.dylib, building for 
macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file 
/opt/homebrew/Cellar/poppler/22.02.0/lib/libpoppler.dylib, building for 
macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file 
/opt/homebrew/Cellar/cairo/1.16.0_5/lib/libcairo.dylib, building for 
macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file 
/opt/homebrew/Cellar/libpng/1.6.37/lib/libpng16.dylib, building for 
macOS-x86_64 but attempting to link with file built for macOS-arm64
+  ld: warning: ignoring file /opt/homebrew/Cellar/zlib/1.2.11/lib/libz.dylib, 
building for macOS-x86_64 but attempting to link with file built for macOS-arm64
+  Undefined symbols for architecture x86_64:
+#+end_example
+
+This happens because M1 architecture is =ARM64=, whereas the Emacs App you are 
using has been compiled for the =x86_64= architecture. The way to solve this 
problem is to install a version of Emacs which has been compiled for the M1. As 
of today, [2022-05-09 Mon], the latest version of Emacs available on 
https://emacsformacosx.com/ is natively compiled and you will not face these 
issues on it. Please remove your current Emacs App and install it from 
https://emacsformacosx.com/.
+
+Thank you.
+
+PS: How do I know if the Emacs I'm running has been compiled correctly?
+
+You can see this by opening the =Activity Monitor=, selecting =Emacs=, 
clicking on the =Info= key, and then clicking on =Sample=. The =Code Type= 
field in the Sample output will show you how your Application has been 
compiled. Here is the output for EmacsForMacOSX (you can see that it's =ARM64=):
+#+begin_example
+  Sampling process 61824 for 3 seconds with 1 millisecond of run time between 
samples
+  Sampling completed, processing symbols...
+  Analysis of sampling Emacs-arm64-11 (pid 61824) every 1 millisecond
+  Process:         Emacs-arm64-11 [61824]
+  Path:            /Applications/Emacs.app/Contents/MacOS/Emacs-arm64-11
+  Load Address:    0x1007f0000
+  Identifier:      org.gnu.Emacs
+  Version:         Version 28.1 (9.0)
+  Code Type:       ARM64
+  Platform:        macOS
+#+end_example
+
+If your Emacs is compiled for x86, the =Code Type= will be =x86_64=.