missing commands: gcov, gcc-ar, gcc-ranlib and others

[sorokin]

Describe the bug
gcc/g++ are not the only commands that are produced by gcc package. There are others. gcov is useful when code coverage need to be computed. gcc-ar/gcc-ranlib are needed when link-time optimization is used.

Apparently newer versions of NixOS don't add these and others gcc commands to system-path/bin.

From what I can see the problem is caused by gcc-wrapper package as it wraps only cpp/gcc/g++ leaving others commands inaccessible.

To Reproduce
In shell running gcov prints "gcov: command not found". Same for other commands provided by gcc package.

Expected behavior
The expected result of running gcov is: "Usage: gcov [OPTION...] SOURCE|OBJ...". Same for other commands.

Metadata
$ shell -p nix-info --run "nix-info -m"
error: attribute 'system' missing, at (string):1:1

• system: 0
• host os: Linux 4.19.90, NixOS, 19.09.git.dc8a496 (Loris)
• multi-user?: no
• sandbox: yes
• version: nix-env (Nix) 2.3
• channels(root): "nixos-14.12.335.676e8d7"
• channels(ivan): "nixos-14.12.801.221101a"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

The NixOS version I run is 19.09 based on commit 83c8fe6.

[matthewbauer]

You can get access to these through gcc.cc and clang.cc. Maybe we should switch these so that "unwrapped" gcc is "gcc" and "wrapped" gcc is known as "gcc-wrapped".

[sorokin]

Thank you for your suggestion. I didn't know I can refer to unwrapped gcc as gcc.cc. I think now I can configure my environment correctly.

Using gcc.cc instead of gcc fixes the problem with gcov program. gcov is installed correctly now. Unfortunately g++ form unwrapped gcc doesn't work (somewhat expectedly). Compiling a simple hello world program prints this linker error:

$ LANG=en_US g++ main.cpp 
/nix/store/ajrrkivdfvp8dp4vdg5hp1h5hblmanc9-binutils-2.31.1/bin/ld: cannot find crt1.o: No such file or directory
/nix/store/ajrrkivdfvp8dp4vdg5hp1h5hblmanc9-binutils-2.31.1/bin/ld: cannot find crti.o: No such file or directory
collect2: error: ld returned 1 exit status

If I build system with both gcc.cc and gcc the same linker error remains. Quick googling showed a thing called package priority. I'll take a look at it. I think using priorities I can configure my system in a way both g++ and gcov work.

In any case I believe the user experience can be improved here. As a user I believe the best name for the package is gcc and it should provide both wrapped gcc/g++ and gcov.

[sorokin]

After reading cc-wrapper/default.nix, I think perhaps something like this would fix my problem:

diff --git a/pkgs/build-support/cc-wrapper/default.nix b/pkgs/build-support/cc-wrapper/default.nix
index 9851602179c..a2709bcb310 100644
--- a/pkgs/build-support/cc-wrapper/default.nix
+++ b/pkgs/build-support/cc-wrapper/default.nix
@@ -209,6 +209,14 @@ stdenv.mkDerivation {
 
     + optionalString cc.langGo or false ''
       wrap ${targetPrefix}gccgo ${./cc-wrapper.sh} $ccPath/${targetPrefix}gccgo
+    ''
+    + optionalString cc.isGNU or false ''
+      ln -s ${targetPrefix}gcc-ar $out/bin/${targetPrefix}gcc-ar
+      ln -s ${targetPrefix}gcc-nm $out/bin/${targetPrefix}gcc-nm
+      ln -s ${targetPrefix}gcc-ranlib $out/bin/${targetPrefix}gcc-ranlib
+      ln -s ${targetPrefix}gcov $out/bin/${targetPrefix}gcov
+      ln -s ${targetPrefix}gcov-dump $out/bin/${targetPrefix}gcov-dump
+      ln -s ${targetPrefix}gcov-tool $out/bin/${targetPrefix}gcov-tool
     '';
 
   strictDeps = true;

Could somebody more familiar with cc-wrapper, comment if this is a reasonable approach?

[stale]

Nixpkgs stale bot info

[siraben]

ping

[stale]

I marked this as stale due to inactivity. → More info

[alarsyo]

Still relevant

[melg8]

I've encountered same issue while building docker image with nix. Still relevant.

[barracuda156]

After reading cc-wrapper/default.nix, I think perhaps something like this would fix my problem:

diff --git a/pkgs/build-support/cc-wrapper/default.nix b/pkgs/build-support/cc-wrapper/default.nix
index 9851602179c..a2709bcb310 100644
--- a/pkgs/build-support/cc-wrapper/default.nix
+++ b/pkgs/build-support/cc-wrapper/default.nix
@@ -209,6 +209,14 @@ stdenv.mkDerivation {
 
     + optionalString cc.langGo or false ''
       wrap ${targetPrefix}gccgo ${./cc-wrapper.sh} $ccPath/${targetPrefix}gccgo
+    ''
+    + optionalString cc.isGNU or false ''
+      ln -s ${targetPrefix}gcc-ar $out/bin/${targetPrefix}gcc-ar
+      ln -s ${targetPrefix}gcc-nm $out/bin/${targetPrefix}gcc-nm
+      ln -s ${targetPrefix}gcc-ranlib $out/bin/${targetPrefix}gcc-ranlib
+      ln -s ${targetPrefix}gcov $out/bin/${targetPrefix}gcov
+      ln -s ${targetPrefix}gcov-dump $out/bin/${targetPrefix}gcov-dump
+      ln -s ${targetPrefix}gcov-tool $out/bin/${targetPrefix}gcov-tool
     '';
 
   strictDeps = true;

Could somebody more familiar with cc-wrapper, comment if this is a reasonable approach?

What to do if these are not available at all, i.e. GCC has been installed that way?