Error while making moongl

[Yaumama]

While building moongl I get this error:

mingw32-make[1]: Entering directory 'D:/CodeProjects/test/moongl/src'
process_begin: CreateProcess(NULL, lua -e "print(string.match(_VERSION, \"%d+%.%d+\") or \"5.3\")", ...) failed.
Makefile:15: pipe: Bad file descriptor
cc -O2 -Wall -Wextra -Wpedantic -DCOMPAT53_PREFIX=moongl_compat_ -std=gnu99 -DLUAVER=5.3 -fpic -DLINUX -I/usr/include -I/usr/include/lua5.3 -I/usr/local/include/lua5.3   -c -o bitfield.o bitfield.c
In file included from internal.h:35,
                 from bitfield.c:26:
moongl.h:33:10: fatal error: lua.h: No such file or directory
   33 | #include <lua.h>
      |          ^~~~~~~
compilation terminated.
mingw32-make[1]: *** [<builtin>: bitfield.o] Error 1
mingw32-make[1]: Leaving directory 'D:/CodeProjects/test/moongl/src'
mingw32-make: *** [Makefile:5: build] Error 2

Can anyone help?

[stetre]

You are compiling for Lua 5.3, but it is either not installed, or it is not in a standard location (the error says that it cannot find the Lua headers, lua.h & C).

[Yaumama]

Thank you, how can I install the header files?

[stetre]

Install Lua 5.3. This also installs the header files.

As an aside, it may be that you have already installed Lua version 5.4, which is the current version. If this is the case, and you want to use this version, you have to compile with the LUAVER=5.4 flag (see here).

[Yaumama]

I installed the Lua 5.3 binaries, but it didn't install the header files. I will try to find a way to install Lua 5.3.

[stetre]

If you are using MSYS2, just follow these instructions. This will install the latest packaged version, which currently is Lua 5.4.

If you really need to use 5.3, though, you should be able to install it from the sources which you can find at www.lua.org. Download the package for the version you are interested in (e.g. lua-5.3.6.tar.gz) , and run these commands from a mingw shell:

$ tar -zxvf lua-5.3.6.tar.gz 
$ cd lua-5.3.6 
$ make mingw
$ make install

[Yaumama]

Now I am getting this error:

D:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lGLEW
collect2.exe: error: ld returned 1 exit status
make[1]: [Makefile:163: moongl] Error 1 (ignored)

make[1]: Leaving directory '/d/CodeProjects/MoonGL/moongl/src'

[stetre]

First of all, I heartily suggest you to follow the installation instructions, step by step. By just following them, you wouldn't get any of these errors. They are written specifically for this purpose.

That said, this last error tells you that the GLEW library (libglew) is missing from your system. The solution is to install libglew, which (as stated in the above instructions) is a required dependency for moongl.

[Yaumama]

I installed glew with msys2 however it still isn't working, I also followed the installation instructions.

[stetre]

It seems that your system isn't recognized as MINGW, but regarded as LINUX instead.

The makefile (src/Makefile) detects that the system is MINGW by checking the MINGW_PREFIX environment variable, which should be predefined. This suggests that the MINGW_PREFIX variable is not defined in the shell you are compiling in.

To check it, run echo $MINGW_PREFIX. This should echo something like \mingw64, if I recall correctly (unfortunately I don't have a windows system at hand to try it out myself). If it echoes nothing, then the variable is not defined and this is the source of the problem. The workaround is to properly define the variable, for example by executing export MINGW_PREFIX=\mingw64 in the shell.

[Yaumama]

echo $MINGW_PREFIX just echoed exactly that "$MINGW_PREFIX". And where should I execute export MINGW_PREFIX=\mingw64?

[stetre]

Are you working in a plain mingw shell? Try echo ${MINGW_PREFIX} instead.

However, you should execute the export command in the shell that you are using to compile the library, like the one you used to install other programs with pacman as per the instructions. The instructions also tell you the shell launcher you should use to execute the shell.

MSYS2 pre-defines a few environment variables, like MINGW_PACKAGE_PREFIX and MINGW_PREFIX. The former is useful to detect if the system is 32 or 64 bit, and thus to select the appropriate package when installing something with pacman. The latter (MINGW_PREFIX) contains the base path for the mingw directory tree. The makefiles for my libraries rely on this variable both to detect that the system is mingw (instead of linux, or macos) and adjust the build commands accordingly, and to decide where to install them when you run make install. I didn't noticed it at first (my bad), but in the first post of this thread you have a -DLINUX passed to the gcc command, which means that the system detection failed and that the makefile 'thinks' it is compiling for a linux system (hence the error, and possibly the other errors you got previously).

[Yaumama]

Oh thanks, it echoed /mingw64! Upon reinstalling gcc and lua, nothing changed.

[stetre]

Do you mean that you still get the -DLINUX flag? That would be very strange.

By the way, another strange thing I noticed in your logs is that Entering directory 'D:/CodeProjects/test/moongl/src' thing. Are you really following the instructions?

[Yaumama]

I'm not getting the -DLINUX flag, I am getting the same glew error. And yes, I am following the instructions

[stetre]

Are you sure about the flag? If the error you get is still cannot find -lGLEW, it likely means that you are still getting the -DLINUX flag. Otherwise, with the correct -DMINGW flag (which is set when MINGW_PREFIX is detected) you wouldn't have -lGLEW in the gcc command (see your first post), but you would have -lglew32 instead, and the error should be resolved.

I really don't know what's going on on your system, but we can try a workaround. Edit src/Makefile, and enter this line at the very top: MINGW_PREFIX=/mingw64 (above the line ifdef MINGW_PREFIX). Then compile again, and let me know the outcome.

EDIT:
Another thing that may have caused the problem is the failure of the LUAVER automatic detection, notified by this error:
process_begin: CreateProcess(NULL, lua -e "print(string.match(_VERSION, \"%d+%.%d+\") or \"5.3\")", ...) failed. Makefile:15: pipe: Bad file descriptor.

If this is actually the culprit, the problem should be solved by just commenting out line 14 in src/Makefile, i.e. by just adding a leading '#' like so:
#LUAVER?=$(shell lua -e 'print(string.match(_VERSION, "%d+%.%d+") or "5.3")'),
and possibly passing the LUAVER at command line if you use a version other than the default 5.3.

Again, let me know if this works. In case, I'll have to fix the makefile in the main branch (and also the makefiles of the other libraries...). Thank you