*.h files recognized as C++ filetype but I am working on a C project.

[ubaldot]

I am working on a C project but ALE recognizes .h files as cpp files.
I am working on

VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Sep 21 2021 22:13:38)
MS-Windows 32-bit console version
Included patches: 1-3452

Here is my ALEInfo

 Current Filetype: cpp
Available Linters: ['cc', 'ccls', 'clangcheck', 'clangd', 'clangtidy', 'clazy', 'cppcheck', 'cpplint', 'cquery', 'flawfinder']
   Linter Aliases:
'cc' -> ['gcc', 'clang', 'g++', 'clang++']
  Enabled Linters: ['cc', 'ccls', 'clangcheck', 'clangd', 'clangtidy', 'clazy', 'cppcheck', 'cpplint', 'cquery', 'flawfinder']
  Ignored Linters: []
 Suggested Fixers: 
  'astyle' - Fix C/C++ with astyle.
  'clang-format' - Fix C/C++ and cuda files with clang-format.
  'clangtidy' - Fix C/C++ and ObjectiveC files with clang-tidy.
  'remove_trailing_lines' - Remove all blank lines at the end of a file.
  'trim_whitespace' - Remove all trailing whitespace characters at the end of every line.
  'uncrustify' - Fix C, C++, C#, ObjectiveC, ObjectiveC++, D, Java, Pawn, and VALA files with uncrustify.
 Linter Variables:

let g:ale_cpp_cc_executable = '<auto>'
let g:ale_cpp_cc_options = '-std=c++14 -Wall'
let g:ale_cpp_ccls_executable = 'ccls'
let g:ale_cpp_ccls_init_options = {}
let g:ale_cpp_clangcheck_executable = 'clang-check'
let g:ale_cpp_clangcheck_options = ''
let g:ale_cpp_clangd_executable = 'clangd'
let g:ale_cpp_clangd_options = ''
let g:ale_cpp_clangtidy_checks = []
let g:ale_cpp_clangtidy_executable = 'clang-tidy'
let g:ale_cpp_clangtidy_extra_options = ''
let g:ale_cpp_clangtidy_options = ''
let g:ale_cpp_clazy_checks = ['level1']
let g:ale_cpp_clazy_executable = 'clazy-standalone'
let g:ale_cpp_clazy_options = ''
let g:ale_cpp_cppcheck_executable = 'cppcheck'
let g:ale_cpp_cppcheck_options = '--enable=style'
let g:ale_cpp_cpplint_executable = 'cpplint'
let g:ale_cpp_cpplint_options = ''
let g:ale_cpp_cquery_cache_directory = 'C:\Users\yt75534\.cache\cquery'
let g:ale_cpp_cquery_executable = 'cquery'
let g:ale_cpp_flawfinder_executable = 'flawfinder'
let g:ale_cpp_flawfinder_minlevel = 1
let g:ale_cpp_flawfinder_options = ''
 Global Variables:

let g:ale_cache_executable_check_failures = v:null
let g:ale_change_sign_column_color = 0
let g:ale_command_wrapper = ''
let g:ale_completion_delay = v:null
let g:ale_completion_enabled = 0
let g:ale_completion_max_suggestions = v:null
let g:ale_disable_lsp = 0
let g:ale_echo_cursor = 1
let g:ale_echo_msg_error_str = 'Error'
let g:ale_echo_msg_format = '%code: %%s'
let g:ale_echo_msg_info_str = 'Info'
let g:ale_echo_msg_warning_str = 'Warning'
let g:ale_enabled = 1
let g:ale_fix_on_save = 0
let g:ale_fixers = {'c': ['astyle', 'clangtidy', 'remove_trailing_lines', 'trim_whitespace']}
let g:ale_history_enabled = 1
let g:ale_history_log_output = 1
let g:ale_keep_list_window_open = 0
let g:ale_lint_delay = 200
let g:ale_lint_on_enter = 1
let g:ale_lint_on_filetype_changed = 1
let g:ale_lint_on_insert_leave = 1
let g:ale_lint_on_save = 1
let g:ale_lint_on_text_changed = 'normal'
let g:ale_linter_aliases = {}
let g:ale_linters = {'c': ['clangtidy'], 'python': ['flake8']}
let g:ale_linters_explicit = 0
let g:ale_linters_ignore = {}
let g:ale_list_vertical = 0
let g:ale_list_window_size = 10
let g:ale_loclist_msg_format = '%code: %%s'
let g:ale_max_buffer_history_size = 20
let g:ale_max_signs = -1
let g:ale_maximum_file_size = v:null
let g:ale_open_list = 0
let g:ale_pattern_options = v:null
let g:ale_pattern_options_enabled = v:null
let g:ale_root = {}
let g:ale_set_balloons = 0
let g:ale_set_highlights = 1
let g:ale_set_loclist = 1
let g:ale_set_quickfix = 0
let g:ale_set_signs = 1
let g:ale_sign_column_always = 0
let g:ale_sign_error = '>>'
let g:ale_sign_info = '--'
let g:ale_sign_offset = 1000000
let g:ale_sign_style_error = '>>'
let g:ale_sign_style_warning = '--'
let g:ale_sign_warning = '--'
let g:ale_sign_highlight_linenrs = 0
let g:ale_statusline_format = v:null
let g:ale_type_map = {}
let g:ale_use_global_executables = v:null
let g:ale_virtualtext_cursor = 0
let g:ale_warn_about_trailing_blank_lines = 1
let g:ale_warn_about_trailing_whitespace = 1
  Command History:

(finished - exit code 0) 'cmd /s/c "clang-tidy c:\PE_Builds\sw-ecu\BSW\software\devices\inclination_sensor_tcm5\src\inclination_spiCommands.h -p C:\PE_Builds\sw-ecu\BSW"'

<<<NO OUTPUT RETURNED>>>

(executable check - failure) clazy-standalone
(executable check - failure) cppcheck
(executable check - failure) cpplint
(executable check - failure) cquery
(executable check - failure) flawfinder
(executable check - failure) ccls
(executable check - failure) cquery
(started) 'cmd /s/c "clangd -compile-commands-dir=C:\PE_Builds\sw-ecu\BSW"'
(executable check - failure) ccls
(executable check - failure) cquery
(finished - exit code 1) 'cmd /s/c "clang++ -S -x c++ -o nul -iquote C:\PE_Builds\sw-ecu\BSW\software\devices\inclination_sensor_tcm5\src -std=c++14 -Wall - < C:\Users\yt75534\AppData\Local\Temp\V3FD253.tmp\inclination_spiCommands.h"'

<<<OUTPUT STARTS>>>
<stdin>:4:10: fatal error: 'vpttypes.h' file not found
#include "vpttypes.h"    /* Data type definition header file */
         ^~~~~~~~~~~~
1 error generated.
<<<OUTPUT ENDS>>>

(executable check - failure) ccls
(finished - exit code 2) 'cmd /s/c "clang-check -analyze C:\MyProjects\Project1\src\MyHeader.h -p C:\PE_Builds\sw-ecu\BSW"'

<<<OUTPUT STARTS>>>
Skipping C:\MyProjects\Project1\src\MyHeader.h. Compile command not found.
<<<OUTPUT ENDS>>>

(finished - exit code 0) 'cmd /s/c "clang-tidy C:\MyProjects\Project1\src\MyHeader.h -p C:\MyProjects\Project1"'

<<<NO OUTPUT RETURNED>>>

(executable check - failure) clazy-standalone
(executable check - failure) cppcheck
(executable check - failure) cpplint
(executable check - failure) cquery
(executable check - failure) flawfinder

[hsanson]

ALE does not recognizes filetypes, it follows whatever vim sets as filetype.
You will have to configure vim to set filetype=c for header files if you want ALE to treat them as c files.

Simplest way is to create an auto command in you config:

augroup filetypedetect
    au! BufRead,BufNewFile *.h         setfiletype c
augroup END

Check :h filetype-overrule for more in deep details.

[shayaniox]

Why the following autocmd doesn't work?

augroup filetypedetect
    au! BufWrite,BufRead,BufNewFile *.h setfiletype c
augroup END

When I write to the buffer, the filetype switches back to cpp.

[Jorenar]

Instead of defining autocommand myself, I rather just use let g:c_syntax_for_h = 1 and let ftdetect script do its job