makefile: used CC=$(CROSS_COMPILE)gcc for CGO compile.

[cfc4n]

Fix bug that prevents compiling jschwinger233/elibpcap package during cross-compilation.

arm64 ubuntu 22.04

/home/cfc4n/project/ecapture $ CROSS_ARCH=amd64 make
make[1]: Leaving directory '/home/cfc4n/project/ecapture/lib/libpcap'
CGO_CFLAGS='-O2 -g -gdwarf-4 -I/home/cfc4n/project/ecapture/lib/libpcap/' CGO_LDFLAGS='-O2 -g -L/home/cfc4n/project/ecapture/lib/libpcap/ -lpcap -static' GOOS=linux GOARCH=amd64 CC=clang go build -tags linux -ldflags "-w -s -X 'ecapture/cli/cmd.GitVersion=linux_amd64:0.7.5-20240303-bfb4a8c:[CORE]' -X 'main.enableCORE=true' " -o bin/ecapture
file bin/ecapture
# github.com/jschwinger233/elibpcap
../../go/pkg/mod/github.com/jschwinger233/elibpcap@v0.0.0-20231010035657-e99300096f5e/elibpcap.go:25:22: undefined: CompileEbpf
bin/ecapture: cannot open `bin/ecapture' (No such file or directory)

Fixed

/home/cfc4n/project/ecapture $ CROSS_ARCH=amd64 make
make[1]: Leaving directory '/home/cfc4n/project/ecapture/lib/libpcap'
CGO_ENABLED=1 CGO_CFLAGS='-O2 -g -gdwarf-4 -I/home/cfc4n/project/ecapture/lib/libpcap/' CGO_LDFLAGS='-O2 -g -L/home/cfc4n/project/ecapture/lib/libpcap/ -lpcap -static' GOOS=linux GOARCH=amd64 CC=x86_64-linux-gnu-gcc go build -tags linux -ldflags "-w -s -X 'ecapture/cli/cmd.GitVersion=linux_amd64:0.7.5-20240303-bfb4a8c:[CORE]' -X 'main.enableCORE=true' -linkmode=external -extldflags -static " -o bin/ecapture
file bin/ecapture
# ecapture
/usr/lib/gcc-cross/x86_64-linux-gnu/11/../../../../x86_64-linux-gnu/bin/ld: /tmp/go-link-3421481706/000004.o: in function `_cgo_9c8efe9babca_C2func_getaddrinfo':
/tmp/go-build/cgo-gcc-prolog:58: warning: Using 'getaddrinfo' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
/usr/lib/gcc-cross/x86_64-linux-gnu/11/../../../../x86_64-linux-gnu/bin/ld: /home/cfc4n/project/ecapture/lib/libpcap//libpcap.a(nametoaddr.o): in function `pcap_nametoaddr':
/home/cfc4n/project/ecapture/lib/libpcap/./nametoaddr.c:181: warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
/usr/lib/gcc-cross/x86_64-linux-gnu/11/../../../../x86_64-linux-gnu/bin/ld: /home/cfc4n/project/ecapture/lib/libpcap//libpcap.a(nametoaddr.o): in function `pcap_nametonetaddr':
/home/cfc4n/project/ecapture/lib/libpcap/./nametoaddr.c:270: warning: Using 'getnetbyname_r' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
/usr/lib/gcc-cross/x86_64-linux-gnu/11/../../../../x86_64-linux-gnu/bin/ld: /home/cfc4n/project/ecapture/lib/libpcap//libpcap.a(nametoaddr.o): in function `pcap_nametoproto':
/home/cfc4n/project/ecapture/lib/libpcap/./nametoaddr.c:527: warning: Using 'getprotobyname_r' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
bin/ecapture: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=048ccf5df926a5aabc7f99c59b33867063b9a2ca, for GNU/Linux 3.2.0, stripped
Fri Apr 12 16:28:59 UTC 2024