[Gcl-devel] WINDOWS -O3 OK - check FIND_INIT and fasload()

[Mike Thomas]

Hi all.

Admittedly the random tester has only made 400 iterations so far and 
I've got to clean up my work this evening, test Maxima etc, but MinGW32 
is now on -O3 with no problems running tha ANSI test.

Every platform that uses "get_extra_bss()" in "sfasl.c" and which has an 
initialisation function in its object files (in my case it is called 
"_init_code" and it calls "do_init()") should be checked to ensure that 
the compiler does not move that initialisation function around in the 
object module, typically with higher order optimisations.

My guess is that the "-freorder-functions" optimisation which is turned 
on by -O2 (MinGW32 gcc at least) is the culprit and theerfore can 
potentially stymie linking code which does not check for such changes.

To check your object, just do:

   objdump -xS your_object_file.o

and redirect to a file which you can view at leisure to see whether your 
initialisation code stays at zero offset or not.

There are only a few IBM headers in the "h" directory which define 
FIND_INIT macro so far but they can be used as an example if you need to 
take action on this.  I will be adding the MinGW32 version tonight 
hopefully.

Thanks for all your help Camm; I am feeling very, very pleased.

Mike Thomas.