As far as I know, the warning comes from a difference in the flags on the section containing C initializers between Visual C++ and Pelles C.
VC++ puts them in a section with read/write access (0xC0000040), whereas Pelles C puts them in the read-only section (0x40000040). Also it appears that Pelles C is merging them with the .rdata section, where VC++ merges them with the .data section.
However I do not know the details of Pelles C, so perhaps Pelle could shed some further light on this?
At any rate, it should not produce any problems other than the warning message when linking
.