Fixed compiler and linker errors

[IsaacHorvath]

This should fix undefined scope errors for fprintf, stdout, and logic_error in glfft, and prevent a multiple definition error for glava_abort and glava_return.

[jobez]

this resolved my build issues as well, thank you for your PR!

[QuLogic]

Seems similar to (but not exactly the same as) #171?

[Nikita240]

+1 fixed my build issues

[jwakely]

This change is correct. Those variables already have a definition in glava/glava.c so these declarations in the header should just be extern.

For why this is necessary since GCC 10, see the changes for -fno-common in the GCC 10 release notes and Porting to GCC 10 page.

[jwakely]

Seems similar to (but not exactly the same as) #171?

This one is correct, that one is wrong.

[shreyasSarve]

thanks for PR

[rdosrun]

this pr fixed my issue thanks

[DanielChicoUGR]

This pr solve the issue for Pop!_OS jammy 22.04 x86_64

[CocolinoFan]

I can confirm this PR solved my issue too. Why is this not merged, it was made almost 4 years ago!
I don't know how to work with a pull request. I had to clone IsaacHorvath's repository and build that.

[DanielChicoUGR]

I can confirm this PR solved my issue too. Why is this not merged, it was made almost 4 years ago!
I don't know how to work with a pull request. I had to clone IsaacHorvath's repository and build that.

Simple,

1. Clone the repository
2. Open the files that the PR modifies
3. Modify the 3 lines that are changed
4. Compile and done

[jwakely]

Modyfing the files by hand seems error prone, and impractical for larger changes. The commands you want are:

git clone https://github.com/jarcode-foss/glava.git
cd glava
git fetch origin refs/pull/185/head
git checkout FETCH_HEAD