"rake ragel" fails with "ragel: -C is an invalid argument"

[junaruga]

Describe the bug

A clear and concise description of what the bug is.

rake ragel fails like this.

$ touch ext/puma_http11/http11_parser.c

$ bundle exec rake ragel
ragel ext/puma_http11/http11_parser.rl -C -G2 -I ext/puma_http11 -o ext/puma_http11/http11_parser.c
ragel: -C is an invalid argument
rake aborted!
Could not build wrapper using Ragel (it failed or not installed?)
/home/jaruga/git/puma/Rakefile:24:in `rescue in block in <top (required)>'
/home/jaruga/git/puma/Rakefile:21:in `block in <top (required)>'
/home/jaruga/git/puma/.bundle/puma/ruby/2.7.0/gems/rake-13.0.1/exe/rake:27:in `<top (required)>'
/usr/local/ruby-2.7.0/bin/bundle:23:in `load'
/usr/local/ruby-2.7.0/bin/bundle:23:in `<main>'

Caused by:
Command failed with status (1): [ragel ext/puma_http11/http11_parser.rl -C ...]
/home/jaruga/git/puma/Rakefile:22:in `block in <top (required)>'
/home/jaruga/git/puma/.bundle/puma/ruby/2.7.0/gems/rake-13.0.1/exe/rake:27:in `<top (required)>'
/usr/local/ruby-2.7.0/bin/bundle:23:in `load'
/usr/local/ruby-2.7.0/bin/bundle:23:in `<main>'
Tasks: TOP => ragel => ext/puma_http11/http11_parser.c
(See full trace by running task with --trace)

Puma config:

Please copy-paste your Puma config AND your command line options here.

I think Puma config is not related to this issue.

To Reproduce

Please add reproduction steps here.

According to the whitequark/parser#317 , ragel >= 7.0.0.9 supports Ruby again.

$ ragel --version
Ragel State Machine Compiler version 7.0.0.12 May 2019
Copyright (c) 2001-2019 by Adrian Thurston

$ bundle install --path=.bundle/puma
$ bundle exec rake compile
$ touch ext/puma_http11/http11_parser.c
$ bundle exec rake ragel

Expected behavior

A clear and concise description of what you expected to happen.

bundle exec rake ragel is executed successfully.

Desktop (please complete the following information):

• OS: Linux Fedora 31
• Puma Version: The latest master branch: 0b737cce42746d8226701520f35685e0624e061b

Note

When I changed the ragel -C with ragel -R seeing the help, it failed with "ragel: -R is an invalid argument".

$ ragel --help
...
host language:
   -C                   C, C++, Obj-C or Obj-C++ (default)
                        All code styles supported.
   --asm --gas-x86-64-sys-v
                        GNU AS, x86_64, System V ABI.
                        Generated in a code style equivalent to -G2
   -D                   D           All code styles supported
   -Z                   Go          All code styles supported
   -A                   C#          -T0 -T1 -F0 -F1 -G0 -G1
   -J                   Java        -T0 -T1 -F0 -F1
   -R                   Ruby        -T0 -T1 -F0 -F1
...

$ git diff
diff --git a/Rakefile b/Rakefile
index 231be50b..c39547a5 100644
--- a/Rakefile
+++ b/Rakefile
@@ -19,7 +19,7 @@ task :ragel
 
 file 'ext/puma_http11/http11_parser.c' => ['ext/puma_http11/http11_parser.rl'] do |t|
   begin
-    sh "ragel #{t.prerequisites.last} -C -G2 -I ext/puma_http11 -o #{t.name}"
+    sh "ragel #{t.prerequisites.last} -R -G2 -I ext/puma_http11 -o #{t.name}"
   rescue
     fail "Could not build wrapper using Ragel (it failed or not installed?)"
   end

$ bundle exec rake ragel
ragel ext/puma_http11/http11_parser.rl -R -G2 -I ext/puma_http11 -o ext/puma_http11/http11_parser.c
ragel: -R is an invalid argument
rake aborted!
Could not build wrapper using Ragel (it failed or not installed?)
/home/jaruga/git/puma/Rakefile:24:in `rescue in block in <top (required)>'
/home/jaruga/git/puma/Rakefile:21:in `block in <top (required)>'
/home/jaruga/git/puma/.bundle/puma/ruby/2.7.0/gems/rake-13.0.1/exe/rake:27:in `<top (required)>'
/usr/local/ruby-2.7.0/bin/bundle:23:in `load'
/usr/local/ruby-2.7.0/bin/bundle:23:in `<main>'

Caused by:
Command failed with status (1): [ragel ext/puma_http11/http11_parser.rl -R ...]
/home/jaruga/git/puma/Rakefile:22:in `block in <top (required)>'
/home/jaruga/git/puma/.bundle/puma/ruby/2.7.0/gems/rake-13.0.1/exe/rake:27:in `<top (required)>'
/usr/local/ruby-2.7.0/bin/bundle:23:in `load'
/usr/local/ruby-2.7.0/bin/bundle:23:in `<main>'
Tasks: TOP => ragel => ext/puma_http11/http11_parser.c
(See full trace by running task with --trace)

[junaruga]

I got the answer here.
whitequark/parser#317 (comment)

The workaround is to use Ragel version 7.0.0.9.

I also found this ticket on Fedora ragel package about this issue.
https://bugzilla.redhat.com/show_bug.cgi?id=1734038

[voxik]

I think this whole is misunderstanding. The upstream Ragel changed their CLI options and they have removed the -C option. So it it is removed from here, the newest Ragel can be used just fine (testing with 7.0.0.12).

But "Ruby support" is out of question, because the parser is in C not in Ruby.

[voxik]

BTW the -C option is still listed among options, while it is not recognized.

$ rpm -q ragel
ragel-7.0.0.12-4.fc33.x86_64

$ ragel -C ext/puma_http11/http11_parser.rl 
ragel: -C is an invalid argument

$ ragel -h
usage: ragel [options] file
general:
   -h, -H, -?, --help   Print this usage and exit
   -v, --version        Print version information and exit
   -o <file>            Write output to <file>
   -s                   Print some statistics and compilation info to stderr
   -d                   Do not remove duplicates from action lists
   -I <dir>             Add <dir> to the list of directories to search
                        for included an imported files
   --rlhc               Show the rlhc command used to compile
   --save-temps         Do not delete intermediate file during compilation
   --no-intermediate    Disable call to rlhc, leave behind intermediate
error reporting format:
   --error-format=gnu   file:line:column: message (default)
   --error-format=msvc  file(line,column): message
fsm minimization:
   -n                   Do not perform minimization
   -m                   Minimize at the end of the compilation
   -l                   Minimize after most operations (default)
   -e                   Minimize after every operation
visualization:
   -V                   Generate a dot file for Graphviz
   -p                   Display printable characters on labels
   -S <spec>            FSM specification to output (for graphviz output)
   -M <machine>         Machine definition/instantiation to output (for
                        graphviz output)
host language:
   -C                   C, C++, Obj-C or Obj-C++ (default)
                        All code styles supported.
   --asm --gas-x86-64-sys-v
                        GNU AS, x86_64, System V ABI.
                        Generated in a code style equivalent to -G2
   -D                   D           All code styles supported
   -Z                   Go          All code styles supported
   -A                   C#          -T0 -T1 -F0 -F1 -G0 -G1
   -J                   Java        -T0 -T1 -F0 -F1
   -R                   Ruby        -T0 -T1 -F0 -F1
   -O                   OCaml       -T0 -T1 -F0 -F1
   -U                   Rust        -T0 -T1 -F0 -F1
   -Y                   Julia       -T0 -T1 -F0 -F1
   -K                   Crack       -T0 -T1 -F0 -F1
   -P                   JavaScript  -T0 -T1 -F0 -F1
line directives:
   -L                   Inhibit writing of #line directives
code style:
   -T0                  Binary search (default)
   -T1                  Binary search with expanded actions 
   -F0                  Flat table
   -F1                  Flat table with expanded actions
   -G0                  Switch-driven
   -G1                  Switch-driven with expanded actions
   -G2                  Goto-driven with expanded actions
large machines:
   --integral-tables    Use integers for table data (default)
   --string-tables      Encode table data into strings for faster host lang
                        compilation
analysis:
   --prior-interaction          Search for condition-based general repetitions
                                that will not function properly due to state mod
                                overlap and must be NFA reps. 
   --conds-depth=D              Search for high-cost conditions inside a prefix
                                of the machine (depth D from start state).
   --state-limit=L              Report fail if number of states exceeds this
                                during compilation.
   --breadth-check=E1,E2,..     Report breadth cost of named entry points and
                                the start state.
   --input-histogram=FN         Input char histogram for breadth check. If
                                unspecified a flat histogram is used.
testing:
   --kelbt-frontend        Compile using original ragel + kelbt frontend
                           Requires ragel be built with ragel + kelbt support
   --colm-frontend         Compile using a colm-based recursive descent
                           frontend
   --reduce-frontend       Compile using a colm-based reducer (default)
   --var-backend           Use the variable-based backend even if the host lang
                           supports goto-based
   --supported-host-langs  Show supported host languages by command line arg
   --supported-frontends   Show supported frontends
   --supported-backends    Show supported backends
   --force-libragel        Cause mainline to behave like libragel