Dependency resolution fails for source with F90 extension

[awvwgk]

Describe the bug

Dependency resolution fails for Fortran source with F90 file extension.

ninja: Entering directory `_build_571'
[1/4] Compiling Fortran object libmain.so.p/src_library.F90.o
FAILED: libmain.so.p/src_library.F90.o 
gfortran -Ilibmain.so.p -I. -I.. -fdiagnostics-color=always -pipe -D_FILE_OFFSET_BITS=64 -Wall -g -fPIC -Jlibmain.so.p -o libmain.so.p/src_library.F90.o -c ../src/library.F90
../src/library.F90:2:8:

    2 |    use accuracy, only : sp, dp
      |        1
Fatal Error: Cannot open module file ‘accuracy.mod’ for reading at (1): No such file or directory
compilation terminated.
[2/4] Module scanner.
ninja: build stopped: dyndep file 'libmain.so.p/depscan.dd' mentions output 'libmain.so.p/src_library.F90.o' whose build statement does not have a dyndep binding for the file.

To Reproduce

Example project reproducing the behaviour:
mwe.tar.gz

Meson log file:
meson-log.txt

Expected behavior

Resolve dependencies independently of file extensions.

system parameters

• Is this a cross build or just a plain native build (for the same computer)?
  native build
• what operating system (e.g. MacOS Catalina, Windows 10, CentOS 8.0, Ubuntu 18.04, etc.)

> conda info

     active environment : mesonbuild
    active env location : /home/awvwgk/miniforge3/envs/mesonbuild
            shell level : 2
       user config file : /home/awvwgk/.condarc
 populated config files : /home/awvwgk/miniforge3/.condarc
          conda version : 4.9.2
    conda-build version : not installed
         python version : 3.7.8.final.0
       virtual packages : __glibc=2.33=0
                          __unix=0=0
                          __archspec=1=x86_64
       base environment : /home/awvwgk/miniforge3  (writable)
           channel URLs : https://conda.anaconda.org/conda-forge/linux-64
                          https://conda.anaconda.org/conda-forge/noarch
          package cache : /home/awvwgk/miniforge3/pkgs
                          /home/awvwgk/.conda/pkgs
       envs directories : /home/awvwgk/miniforge3/envs
                          /home/awvwgk/.conda/envs
               platform : linux-64
             user-agent : conda/4.9.2 requests/2.24.0 CPython/3.7.8 Linux/5.9.16-1-MANJARO manjaro/20.2.1 glibc/2.33
                UID:GID : 1000:1000
             netrc file : None
           offline mode : False

> uname -a
Linux saw8203 5.9.16-1-MANJARO #1 SMP PREEMPT Mon Dec 21 22:00:46 UTC 2020 x86_64 GNU/Linux

• what Python version are you using e.g. 3.8.0
• what meson --version
• what ninja --version if it's a Ninja build

conda list
# packages in environment at /home/awvwgk/miniforge3/envs/mesonbuild:
#
# Name                    Version                   Build  Channel
_libgcc_mutex             0.1                 conda_forge    conda-forge
_openmp_mutex             4.5                       1_gnu    conda-forge
ca-certificates           2020.12.5            ha878542_0    conda-forge
certifi                   2020.12.5        py37h89c1867_1    conda-forge
ld_impl_linux-64          2.35.1               hea4e1c9_2    conda-forge
libffi                    3.2.1             he1b5a44_1007    conda-forge
libgcc-ng                 9.3.0               h2828fa1_18    conda-forge
libgomp                   9.3.0               h2828fa1_18    conda-forge
libstdcxx-ng              9.3.0               h6de172a_18    conda-forge
meson                     0.57.1             pyhd8ed1ab_0    conda-forge
ncurses                   6.2                  h58526e2_4    conda-forge
ninja                     1.10.2               h4bd325d_0    conda-forge
openssl                   1.1.1j               h7f98852_0    conda-forge
pip                       21.0.1             pyhd8ed1ab_0    conda-forge
python                    3.7.8           h6f2ec95_0_cpython    conda-forge
python_abi                3.7                     1_cp37m    conda-forge
readline                  8.0                  he28a2e2_2    conda-forge
setuptools                49.6.0           py37h89c1867_3    conda-forge
sqlite                    3.34.0               h74cdb3f_0    conda-forge
tk                        8.6.10               hed695b0_1    conda-forge
wheel                     0.36.2             pyhd3deb0d_0    conda-forge
xz                        5.2.5                h516909a_1    conda-forge
zlib                      1.2.11            h516909a_1010    conda-forge
> meson --version
0.57.1
> python --version
Python 3.7.8
> ninja --version
1.10.2

[awvwgk]

Is there any way I can assist with fixing this issue? I have some interest in seeing this issue fixed since it blocks adaption of meson 0.57.1 for almost all my projects.

[xclaesse]

A first step would be to write a test case that reproduce the bug, and bisect to know which commit exactly broke it. Check what is different in the command line between a build that works and one that fails.

[awvwgk]

@xclaesse The bug was introduced with the module scanner and only partly fixed after I first reported it, see #8377 (comment).

[awvwgk]

Bisect says the bug was introduced with 2f836e3

[awvwgk]

For a quick hack it seems like adding the F90 file extension in mesonbuild/compiler/compilers.py resolves the issue:

diff --git a/mesonbuild/compilers/compilers.py b/mesonbuild/compilers/compilers.py
index af76ea460..df286e25d 100644
--- a/mesonbuild/compilers/compilers.py
+++ b/mesonbuild/compilers/compilers.py
@@ -55,7 +55,7 @@ lang_suffixes = {
     'cuda': ('cu',),
     # f90, f95, f03, f08 are for free-form fortran ('f90' recommended)
     # f, for, ftn, fpp are for fixed-form fortran ('f' or 'for' recommended)
-    'fortran': ('f90', 'f95', 'f03', 'f08', 'f', 'for', 'ftn', 'fpp'),
+    'fortran': ('f90', 'f95', 'f03', 'f08', 'f', 'for', 'ftn', 'fpp', 'F90'),
     'd': ('d', 'di'),
     'objc': ('m',),
     'objcpp': ('mm',),

I wonder if adding F90, F95, F03, F08, F, FOR, FTN and FPP would work as fix or if the file extension should be considered in a case-insensitive way for Fortran instead.

Edit: See fortran-lang/fpm#250 for the complete list of Fortran file extensions.

[jpakkane]

Can you test if the linked MR fixes the issue for you?

[awvwgk]

Awesome, 9b76036 fixes the above example and can again build all my projects 🎉