Crash on the chinese Win10 with multimarkdown-6

When 'export', 'preview' a md file with markdown-mode with multimarkdown-6, it will consume all the memory then crash the OS (Windows)!

But running the multimarkdown command directly with the same file works fine.

Expected Behavior

At least it should not crash the OS.

Actual Behavior

The multimarkdown process consumes all the memory (16G) and crashes the OS (Win7, Win10).

Steps to Reproduce

1. Running on Chinese Win7 or Win10
2. Installed multimarkdown-6 (6.3.0)
3. Load markdown-mode with following configurations

   (require 'markdown-mode)
   (setq markdown-command "multimarkdown") ;
   (autoload 'gfm-mode "markdown-mode"
      "Major mode for editing GitHub Flavored Markdown files" t)
   (setq markdown-fontify-code-blocks-natively nil)
   (setq markdown-xhtml-header-content "about 300K JS/CSS content")

4. Open any md doc (UTF-8 encoded)
5. Do 'export' or 'preview'
6. Then Cpu starts flying~~ (win7 will halt without any chance, while win10 will allow some while to kill the process)

Backtrace

No backtrace could not be found since the OS crashed.

Software Versions

• Markdown Mode: From Git on 2017-10-17, 2.4-dev, and 2.3 (suffered a long time)
• Emacs: 25.3.1, 25.2, 225.1-2 (x86_64 from GNU)
• OS: Win7, Win10
• Multimarkdown: 6.3.0, 6.2.3, 6.2.2, 6.2.1, 5.4.0

Temporary Solution

1. .emacs, setting encoding for multimarkdown process

   (when (eq system-type 'windows-nt)
     (set-default 'process-coding-system-alist
       '(
         ("[pP][lL][iI][nN][kK]" gbk )
         ("[mM][uU][lL][tT][iI][mM][aA][rR][kK][dD][oO][wW][nN]" utf-8 )
         ("[cC][mM][dD][pP][rR][oO][xX][yY]" gbk . gbk)
         )))

2. markdown-mode.el, change to call the multimarkdown.exe directly.
   Find the line (call-process-region, then change to

   (if (eq system-type 'windows-nt)
     (call-process-region begin-region end-region
                        markdown-command nil buf nil)
     (call-process-region begin-region end-region
                        shell-file-name nil buf nil
                        shell-command-switch markdown-command))

[jrblevin]

It seems avoiding the shell is the solution. I'm not sure there is a reason we need to use the shell anyway, so perhaps we can drop the if conditional and just call markdown-command directly in all cases. Anyone see a problem with doing that?

[syohex]

It seems avoiding the shell is the solution. I'm not sure there is a reason we need to use the shell anyway, so perhaps we can drop the if conditional and just call markdown-command directly in all cases. Anyone see a problem with doing that?

I suppose we can use markdown-command directly. It was introduced by me. I cannot remember in detail, I suppose original code used shell-command-on-region so I replaced it with sh -c.

BTW I cannot reproduce this issue with Japanese UTF-8 text on Windows 10. (I don't have Windows Chinese version)

[syohex]

I confirmed using markdown-command directly works well both on Windows and Linux

[syohex]

I have merged #471. Please check latest version if you still have issue, please reopen this issue.