have_library: checking for main() in -lsocket... -------------------- no

"gcc -o conftest -I. -I/opt/alt/ruby18/lib64/ruby/1.8/x86_64-linux -I.    -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection conftest.c  -L. -L/opt/alt/ruby18/lib64 -Wl,-R/opt/alt/ruby18/lib64 -L. -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -L/opt/alt/openssl/lib64 -L/opt/alt/ruby18/lib64 -Wl,-rpath=/opt/alt/openssl/lib64,-rpath=/opt/alt/ruby18/lib64 -rdynamic -Wl,-export-dynamic     -lruby-static -lsocket  -lpthread -lrt -ldl -lcrypt -lm   -lc"
conftest.c: In function 't':
conftest.c:3:28: warning: variable 'p' set but not used [-Wunused-but-set-variable]
 int t() { void ((*volatile p)()); p = (void ((*)()))main; return 0; }
                            ^
/usr/bin/ld: cannot find -lsocket
collect2: error: ld returned 1 exit status
checked program was:
/* begin */
1: /*top*/
2: int main() { return 0; }
3: int t() { void ((*volatile p)()); p = (void ((*)()))main; return 0; }
/* end */

"gcc -o conftest -I. -I/opt/alt/ruby18/lib64/ruby/1.8/x86_64-linux -I.    -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection conftest.c  -L. -L/opt/alt/ruby18/lib64 -Wl,-R/opt/alt/ruby18/lib64 -L. -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -L/opt/alt/openssl/lib64 -L/opt/alt/ruby18/lib64 -Wl,-rpath=/opt/alt/openssl/lib64,-rpath=/opt/alt/ruby18/lib64 -rdynamic -Wl,-export-dynamic     -lruby-static -lsocket  -lpthread -lrt -ldl -lcrypt -lm   -lc"
/usr/bin/ld: cannot find -lsocket
collect2: error: ld returned 1 exit status
checked program was:
/* begin */
1: /*top*/
2: int main() { return 0; }
3: int t() { main(); return 0; }
/* end */

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