[ros-dev] msvcrt/crtdll "merge"

[Gunnar Dalsnes]

Waldo Alvarez Cañizares wrote:
> Hi Gunnar:
>  
> Great!    less duplicated code == better code
>  
> I had planning to report this about msvcrt/crtdll the first chance I could get to read my e-mail, but now that you talked then there's no better chance than this I think. I was playing with msvcrt dll a couple of days ago because I was trying to test some apps against it and to maybe find some of the multithreading issues it contains. Well I dropped it because I really had no time but one thing I noticed is that there are some entries in the .def file something like this strlen=ntdll.strlen only strings routines if I remember well. Now after I got the binary file (.dll) I was inspecting it with LordPE, a tool to sniff every detail of PE's and saw that actually those routines are not imported by crtdll (maybe because of the strings.a statically linked) also I saw that msvcrt.dll is importing functions from itself funny that is something I never saw before (Is ROS parsing the exports table before the imports one? Just curious). But worst there are 2 references to msvcrt with
 different functions that the -O flag when passed to the linker can't fix. I have seen this before in some applications compiled with mingw (freecraft for example. Could be this an unnoticed bug in mingw's linker?  If It is, it doesn't harm but it sucks to not have it the better way you can if it is easy to do it). btw I was also looking for string routines exported by ntdll in order to squeeze a bit more both libraries and noticed in XP's ntdll some functions that at the beginning I thought were mistyped (It would not be the first time) but when I took a look at msdn Tada! WindowsCE functions, nothing about XP/2k... but there they ARE. Please do not forget to fix those problems with exports if you can, or anyone with a chance, those libraries stink a lot. I still don't understand every detail on how the whole thing works: build system, linker... so this is a "I don't know how to fix", at least for now.
>  

I made some changes so neither crtdll/msvcrt import from self anymore. 
Its strange that the linker is not smart enough to resolve symbols 
without having to import from self, but it could be "by design".

The linker is crazy, because it does not complain when you export 
non-existing symbols/functions. Anyone who calls these functions will 
crash in mysterious ways (been there). The bug might be triggered by the 
option --enable-stdcall-fixup??? (just guessing)

And about the strlen=ntdll.strlen stuff. Forwarded functions doesnt show 
up as imported because they arent really imported, so this is normal.

Dont understand what XP's ntdll exporting "WindowsCE" functions has to 
do with anything?

Gunnar