C compiler not found, but GCC is installed

Question

I have a fresh install of a Slackware64 14.0 on a dedicate server and I'm having a hard time to compile nginx.

./configure (my options)

returns

checking for OS
 + Linux 3.10.23-xxxx-std-ipv6-64 x86_64
checking for C compiler ... not found

./configure: error: C compiler cc is not found

but gcc is installed, as this is what gcc -v returns:

Reading specs from /usr/lib64/gcc/x86_64-slackware-linux/4.7.1/specs
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-slackware-linux/4.7.1/lto-wrapper
Target: x86_64-slackware-linux
Configured with: ../gcc-4.7.1/configure --prefix=/usr --libdir=/usr/lib64 --mandir=/usr/man --infodir=/usr/info --enable-shared --enable-bootstrap --enable-languages=ada,c,c++,fortran,go,java,lto,objc --enable-threads=posix --enable-checking=release --enable-objc-gc --with-system-zlib --with-python-dir=/lib64/python2.7/site-packages --disable-libunwind-exceptions --enable-__cxa_atexit --enable-libssp --enable-lto --with-gnu-ld --verbose --enable-java-home --with-java-home=/usr/lib64/jvm/jre --with-jvm-root-dir=/usr/lib64/jvm --with-jvm-jar-dir=/usr/lib64/jvm/jvm-exports --with-arch-directory=amd64 --with-antlr-jar=/home/slackware/slackbuilds/gcc/antlr-runtime-3.4.jar --enable-multilib --target=x86_64-slackware-linux --build=x86_64-slackware-linux --host=x86_64-slackware-linux
Thread model: posix
gcc version 4.7.1 (GCC) 

What I tried (after googling)

"/tmp is mounted with noexec."
Indeed it was, as part of my hardening configurations. I changed it and reboot to make sure, now my /etc/fstab looks like this:

# <file system> <mount point>   <type>  <options>   <dump>  <pass>
/dev/md1    /   ext4    errors=remount-ro,discard   0   1
/dev/md2    /home   ext4    defaults,discard    1   2
/dev/md5    /var/www    ext4    defaults,discard    1   2
/dev/md6    /var/log    ext4    defaults,discard    1   2
/dev/md7    /tmp    ext4    defaults,discard,nodev,nosuid   1   2
/dev/md8    /var/lib/mysql  ext4    defaults,discard    1   2
/dev/sda3   swap    swap    defaults    0   0
/dev/sdb3   swap    swap    defaults    0   0
proc            /proc   proc    defaults        0       0
sysfs           /sys    sysfs   defaults        0       0
/tmp            /var/tmp none   rw,nosuid,nodev,bind    0   0

The new fstab without noexec does not work though. (I even tried with explicit exec)

"gcc is not on your $PATH"
It is.

whereis gcc
gcc: /usr/bin/gcc /usr/lib64/gcc /usr/X11R6/bin/gcc /usr/bin/X11/gcc /usr/X11/bin/gcc /usr/libexec/gcc /usr/man/man1/gcc.1.gz /usr/share/man/man1/gcc.1.gz /usr/X11/man/man1/gcc.1.gz

echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/usr/sbin:/bin:/usr/bin

Other things I did:

Looking nginx configure file, they make use of a CC var. This CC did not exist.

CC=/usr/bin/gcc

This did not work too.

I tried compiling another program from source to make sure this is not nginx problem, and I found something interesting maybe:

By trying to compile htop, I got this:

./configure 

checking for gcc... gcc
checking whether the C compiler works... no
configure: error: in `/home/napster/htop-master':
configure: error: C compiler cannot create executables
See `config.log' for more details

Which is expected, because even though I have a minimal installation without most deveveloper tools, the gcc is found. This error should be solved by installing the required tool.

I even checked symbolic links on /usr/bin to make sure gcc and cc are ok:

ls -l /usr/bin

cc -> gcc
gcc -> gcc-4.7.1

Any ideas?
Thanks in advance.

Answer 1

What are the contents of the 'config.log' file?

Most likely you're picking up some bad CFLAGS or LDFLAGS somewhere -- possibly in the config script or from nginx/htop defaults.

CFLAGS and LDFLAGS are options passed to the compiler's command line. If they're invalid then the compiler won't run.

The same symptom could result if you're missing a basic library that nginx/htop needs and the LDFLAG that specifies that is causing gcc to bail out.

You really need to check the config.log file.

Answer 2

When I encountered this, the problem was that I had specified the build directory as --builddir=~/git/nginx/build.

After seeing the error, I looked in the file ~/git/nginx/build/autoconf.err and saw the message:

cc1: fatal error: /home/aaron/git/nginx/build/autotest.c: No such file or directory
compilation terminated.

This seemed strange. Then I noticed a rogue directory, named ~, had appeared!

A quick rm -fr \~/ got rid of it, and then I ran auto/configure again but with an absolute path for --builddir and it worked.

Answer 3

Pass --with-cc option to configure.

See http://nginx.org/en/docs/configure.html for details.

Answer 4

I think maybe it is the permission problem. I use sudo ./configure it will be OK.