Re: Compilation problems with latest MSVC

[Jason Rumney <jasonr@gnu.org>]

Eli Zaretskii wrote:
>> Date: Fri, 29 Dec 2006 23:43:17 +0000
>> From: Jason Rumney <jasonr@gnu.org>
>> Cc: drobinow@gmail.com, emacs-devel@gnu.org
>>
>> The crash is happening within the initialization code before any Emacs 
>> code gets run (__tmainCRTStartup). This code is calling _free_internal, 
>> which we are redefining in gmalloc.c.
>>     
>
> That rings a bell: during linking, the linker complained about
> multiple definitions of some memory-related functions, I think calloc
> and realloc.  Did you have those warnings in your build?
>   
Yes, they appear as errors if you link against libcmt.lib, unless you 
include -force:multiple in LINK_FLAGS. I suspect that the single 
threaded library is required for Emacs, as the multithreaded library 
will be allocating heap memory for each thread behind your back to avoid 
problems with global variables, so there will always be a conflict 
between Emacs's and the C library's malloc routines.

I also tried linking against msvcrt.lib (the dynamic linked version of 
libcmt). It doesn't complain about the multiple definitions, but there 
are more unresolved symbols. I also recall Andrew Innes trying in the 
past to get Emacs working with the dynamic linked c runtime, I'm not 
sure if he succeeded in the end by ensuring that Emacs's memory 
allocations do not intertwine with the system library's or whether he 
gave up.