How to install Nokogiri using gcc on MacOS Catalina - ruby

Question

I am trying to install Nokogiri on my MacOS Catalina 10.15.1 system.
gem install nokogiri
The error in the log file is:
"gcc -o conftest -I/Users/shairyar/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0/x86_64-darwin18 -I/Users/shairyar/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0/ruby/backward -I/Users/shairyar/.rvm/rubies/ruby-2.6.3/include/ruby-2.6.0 -I. -I/usr/local/opt/readline/include -I/usr/local/opt/libyaml/include -I/usr/local/opt/readline/include -I/usr/local/opt/libksba/include -I/usr/local/opt/openssl#1.1/include -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -D_DARWIN_UNLIMITED_SELECT -D_REENTRANT -O3 -ggdb3 -Wall -Wextra -Wdeclaration-after-statement -Wdeprecated-declarations -Wdivision-by-zero -Wimplicit-function-declaration -Wimplicit-int -Wpointer-arith -Wshorten-64-to-32 -Wwrite-strings -Wmissing-noreturn -Wno-constant-logical-operand -Wno-long-long -Wno-missing-field-initializers -Wno-overlength-strings -Wno-parentheses-equality -Wno-self-assign -Wno-tautological-compare -Wno-unused-parameter -Wno-unused-value -Wunused-variable -Wextra-tokens -fno-common -pipe -I /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/libxml2 conftest.c -L. -L/Users/shairyar/.rvm/rubies/ruby-2.6.3/lib -L/usr/local/opt/libyaml/lib -L/usr/local/opt/readline/lib -L/usr/local/opt/libksba/lib -L/usr/local/opt/openssl#1.1/lib -L. -L/usr/local/opt/readline/lib -fstack-protector-strong -L/usr/local/lib -L/usr/local/opt/libyaml/lib -L/usr/local/opt/readline/lib -L/usr/local/opt/libksba/lib -L/usr/local/opt/openssl#1.1/lib -lruby.2.6 "
gcc: error: unrecognized command line option '-Wdivision-by-zero'; did you mean '-Wdiv-by-zero'?
gcc: error: unrecognized command line option '-Wshorten-64-to-32'
gcc: error: unrecognized command line option '-Wextra-tokens'; did you mean '-Wextra-semi'?
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: int main(int argc, char **argv)
4: {
5: return 0;
6: }
/* end */
I have been searching and tried installing gcc using brew install gcc and brew link gcc but that does not help.
Here is the gcc version I have:
$which gcc
/usr/local/bin/gcc
$gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-apple-darwin19/9.2.0/lto-wrapper
Target: x86_64-apple-darwin19
Configured with: ../gcc-9.2.0/configure --build=x86_64-apple-darwin19 --disable-nls --enable-checking=release --with-system-zlib --disable-multilib --with-sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk --enable-languages=c,c++,fortran --with-gmp=/usr/local --with-mpc=/usr/local --with-mpfr=/usr/local
Thread model: posix
gcc version 9.2.0 (GCC)
I also tried the following which did not work:
gem install nokogiri -- --use-system-libraries
CC=llvm-gcc gem install nokogiri

Answer 1

To solve the problem I deleted the gcc I installed, located at /usr/local/bin/gcc, and that seems to have solved my problem. When I ran the command
which gcc
the output I got was:
/usr/local/bin/gcc
I needed the one that Apple installed located at /usr/bin/gcc.