Fix undefined symbol: lround in libxt_setset.so

[Copilot]

The shared library fails to load with undefined symbol: lround because the math library isn't linked despite using lround() from <math.h>.

Changes

src/Makefile.in

• Add -lm to link the math library
• Add -Wl,--no-as-needed to force libm.so.6 into NEEDED dependencies (modern GCC's --as-needed was stripping it)

src/libxt_setset.c

• Change void _init(void) to static void __attribute__((constructor)) _init(void) to avoid symbol conflict with system _init in modern GCC shared libraries

 %.so: %_sh.o
-	gcc -shared -lxtables -o $@ $<
+	gcc -shared -Wl,--no-as-needed -lxtables -lm -o $@ $<

Warning

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Original prompt

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This section details on the original issue you should resolve

<issue_title>Fix lround error</issue_title>
<issue_description>Fix

/usr/lib/x86_64-linux-gnu/xtables/libxt_setset.so: /usr/lib/x86_64-linux-gnu/xtables/libxt_setset.so: undefined symbol: lround</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Fix lround error #4

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