NAME

Perl5::Build::Warnings - Parse make output for build-time warnings

SYNOPSIS

    use Perl5::Build::Warnings;

    my $self = Perl5::Build::Warnings->new( { file => '/path/to/make.log' } );

    my $hashref = $self->get_warnings_groups;

    my $arrayref = $self->get_warnings;

    $self->report_warnings_groups;

DESCRIPTION

Perl5::Build::Warnings is a module for use in studying build-time warnings emitted by make when building the Perl 5 core distribution from source code.

Prerequisites

CPAN module Capture::Tiny is used in this library's test suite, but not in the module itself. There are currently no other prerequisites not found in the Perl 5 core distribution.

Assumptions

Logging of make Output

The module assumes that the user has logged the output of make (or make test_prep -- but not make test -- or Windows equivalents) to a plain-text file. Something like:

    make test_prep 2>&1 > /path/to/make.log

Format for Build-Time Warnings

The module assumes that within such a logfile, warnings are recorded in this format:

    op.c:5468:34: warning: argument ‘o’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Wclobbered]

That is,

    <filename>:<line_numbert>:<character_number>: warning: <warning_description> [-<Wwarning_class>]

Note that the first field recorded, filename may be either the basename of a file in the top-level of the source code or a relative path to a file beneath the top-level.

Note further that the last field recorded, the class of warning, starts with an open bracket ([), followed by a hyphen and an upper-case 'W' (-W), followed by the warning class, followed by a close bracket (]). In this module we will ignore the open and close brackets and the hyphen, but we will capture and report the upper-case 'W'. Hence, whereas the log will record

    [-Wclobbered]

... this module will store and report that information as:

    Wclobbered

This is done in part because we may wish to use this data on the command-line and the hyphen is likely to be significant to the shell.

METHODS

new()

• Purpose

  Perl5::Build::Warnings constructor.

• Arguments

      $file = "./t/data/make.g++-8-list-util-fallthrough.output.txt";
      $self = Perl5::Build::Warnings->new( { file => $file } );

  Single hash reference with one required element, file, whose value is a path to a file holding a log of make's output.

• Return Value

  Perl5::Build::Warnings object.

get_warnings_groups()

• Purpose

  Identify the types of build-time warnings found in the make log and the number of each such type.

• Arguments

      $hashref = $self->get_warnings_groups();

  None.

• Return Value

  Reference to a hash whose elements are keyed on warnings classes (e.g., Wclobbered). The value of each element is the number of times such class appeared in the file.

report_warnings_groups()

• Purpose

  Pretty-print to STDOUT the information returned by get_warnings_groups.

• Arguments

      $self->report_warnings_groups;

  None.

• Return Value

  Implicitly returns a Perl-true value.

• Comment

  The information reported will appear as below, but may change in the future.

      Wcast-function-type                        6
      Wclobbered                                 2
      Wformat-overflow=                          2
      Wignored-qualifiers                        4
      Wimplicit-fallthrough=                    32
      Wmultistatement-macros                     1
      Wpragmas                                   3

get_warnings()

• Purpose

  Generate a list of all warnings.

• Arguments

      $arrayref = $self->get_warnings();

• Return Value

  Array reference, each element of which is a reference hash holding a parsing of the elements of an individual warning.

BUGS

None reported so far. The author prefers patches filed at http://rt.cpan.org rather than pull requests at github.

AUTHOR

    James E Keenan
    CPAN ID: JKEENAN
    jkeenan@cpan.org
    http://thenceforward.net/perl/modules/Perl5-Parse-MakeLog-Warnings

COPYRIGHT

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

The full text of the license can be found in the LICENSE file included with this module.

SEE ALSO

perl(1).

cpanm Perl5::Build::Warnings

perl -MCPAN -e shell
install Perl5::Build::Warnings