I'm confused about the usage of crt0.s in newlib.

[Cliff]

Hi:
    When building,the makefile 
shows that /sys/crt0.s
    is linked into libraries.And 
after libc.a lim.a is
    created,we can link functions in theses 
library like 
    this.
    $crossgcc -o xxx.exe crt0.o 
xxxtest.o -lc -lm ...
    

    My question is:
    1.What's the 
difference in these two crt0.s
    2.Why newlib still need a 
crt0.s
 
    Thanks a 
lot!      
 
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