How to fix "No manual entry for gcc"?

Question

I somehow lost the man pages for gcc and g++. I'm not sure where/what to look for. I'm pretty sure the man pages used to work some time ago. It also works on my Mac at work where I use roughly the same setup. Could it be a problem with brew? Or is it a bug in the XCode Command Line Tools?

Update: I just tried to re-install the XCode Command Line Tools. No luck.

~
✓  man gcc
No manual entry for gcc

~
✗  which gcc
/usr/bin/gcc

~
✓  gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
Target: x86_64-apple-darwin13.1.0
Thread model: posix

Tanatanach

You may want to try asking on Superuser as that site will probably have better help for issues involving tools – Vermilion

does man work for other things... – Clothing

@GradyPlayer yes it does. It works with unrar which I installed using brew. – Tanatanach

oh actually new XCODE doesn't really have gcc, gcc is only a symlink to clang try man clang – Clothing

Answer 1

gcc isn't installed anymore by Xcode, it really installs clang and calls it gcc

usxxplayegm1:~ grady$ which gcc
/usr/bin/gcc

usxxplayegm1:~ grady$ /usr/bin/gcc --version

Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 5.1 (clang-503.0.38) (based on LLVM 3.4svn)
Target: x86_64-apple-darwin13.0.2
Thread model: posix

you need man clang

I thought it was a symlink, but ls -l doesn't list it as a symlink, so either it is a hard link or some other sort of trickery.

Clothing

@PaulJ.Lucas after Xcode is installed it should just be available... but you can also reference the file directly.... man /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/share/man/man1/clang.1 – Clothing

Thanks! I wasn't finding it because that path wasn't in my MANPATH. It's not listed in either /etc/manpaths or in /etc/manpaths.d. So how does your system find it? Or do you just explicitly add it to your MANPATH yourself? – Brahmi

if you either install the command line tools (older versions), or just install and use the newer Xcode it should be automagical – Clothing

I've figured out that if MANPATH is unset, then it works. Obviously if one explicitly sets MANPATH in one's .profile (and it doesn't include the path leading to clang.1) then it won't work. Do you know how man is told what paths to use when MANPATH is unset? – Brahmi

@PaulJ.Lucas read 'man man' section SEARCH PATH FOR MANUAL PAGES – Clothing

I read it and looked at /etc/man.conf. Nothing is says explains how it finds a man page buried deep inside the Xcode bundle; yet it does. – Brahmi

yeah it looks like it is hard coded magic... try man -d clang – Clothing

Answer 2

This may be old and doesn't quite answers your concrete question, but I found myself in the same problem with Kali Linux and I solved it with this command, maybe is useful for someone:

apt install gcc-doc

Oosperm

Answer 3

Look at how you set MANPATH in your .profile. Instead of, e.g.,

export MANPATH=/opt/local/man:/usr/local/man

you should do

export MANPATH="/opt/local/man:/usr/local/man:$MANPATH"

And then (breathe) open a new Terminal window.

This way your .profile isn't wiping out (or reflecting an old version of) the system's way of setting MANPATH, which is modified when you install (or reinstall) Xcode.

Kirkuk

Answer 4

I use High Sierra with g++ 7.2 port. Setting MANPATH environment to /opt/local/man (or to /opt/local/man/man1 where g++.gz is found) did not work. So, after ensuring that the soft link g++.gz points to g++-mp-7.1.gz (there was not a g++-mp-7.2.gz in the man1 directory though g++7.2 is my version), I always use the command:

man /opt/local/share/man/man1/g++.gz

that never fails. You can store an alias for this in your .profile, if you are frequently using the man command for g++.

Plassey

Answer 5

For anyone who stumbles upon this currently (like I did), I found that I needed to locate my version of gcc (which I had installed with brew). This is annoying when gcc --version gives the clang version instead! To find the correct gcc version, run

$ ls /usr/local/opt/gcc/bin | grep gcc
gcc-10
gcc-ar-10
gcc-nm-10
...

So I had gcc-10. Whenever you wish to use gcc just replace it with gcc-10, e.g. man gcc-10. Of course you could write an alias for gcc to gcc-10, but this probably is not a great idea, as Xcode seems to rely on the gcc --> clang (hard?) link.

Savdeep