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@haampie
Created January 25, 2022 23:53
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runtime linker
all: exef1 exef2 exef3
EI_OSABI:=7
EI_ABIVERSION:=8
EI_PAD:=9
libf1.so:
echo 'int f(){ return 1; }' | $(CC) -o $@ -shared -Wl,-soname,$@ -x c -
printf '\x0B' | dd of=$@ bs=1 seek=$(EI_OSABI) count=1 conv=notrunc status=none
libf2.so:
echo 'int f(){ return 2; }' | $(CC) -o $@ -shared -Wl,-soname,$@ -x c -
printf '\xff' | dd of=$@ bs=1 seek=$(EI_ABIVERSION) count=1 conv=notrunc status=none
libf3.so:
echo 'int f(){ return 3; }' | $(CC) -o $@ -shared -Wl,-soname,$@ -x c -
printf '\xff' | dd of=$@ bs=1 seek=$(EI_PAD) count=1 conv=notrunc status=none
exef1: libf1.so
echo 'int f(); int main(){printf("%d\\n", f());}' | $(CC) -include stdio.h -o $@ '-Wl,-rpath,$$ORIGIN' -x c - -L. -lf1
exef2: libf2.so
echo 'int f(); int main(){printf("%d\\n", f());}' | $(CC) -include stdio.h -o $@ '-Wl,-rpath,$$ORIGIN' -x c - -L. -lf2
exef3: libf3.so
echo 'int f(); int main(){printf("%d\\n", f());}' | $(CC) -include stdio.h -o $@ '-Wl,-rpath,$$ORIGIN' -x c - -L. -lf3
clean:
rm -f -- *.so exe*
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