RUBY_DEBUG_LOG: Logging debug information mechanism (#3279)

* RUBY_DEBUG_LOG: Logging debug information mechanism

This feature provides a mechanism to store logging information
to a file, stderr or memory space with simple macros.

The following information will be stored.
  * (1) __FILE__, __LINE__ in C
  * (2) __FILE__, __LINE__ in Ruby
  * (3) __func__ in C (message title)
  * (4) given string with sprintf format
  * (5) Thread number (if multiple threads are running)

This feature is enabled only USE_RUBY_DEBUG_LOG is enabled.
Release version should not enable it.

Running with the `RUBY_DEBUG_LOG` environment variable enables
this feature.

  # logging into a file
  RUBY_DEBUG_LOG=/path/to/file STDERR

  # logging into STDERR
  RUBY_DEBUG_LOG=stderr

  # logging into memory space (check with a debugger)
  # It will help if the timing is important.
  RUBY_DEBUG_LOG=mem

RUBY_DEBUG_LOG_FILTER environment variable can specify the fileter string.
If "(3) __func__ in C (message title)" contains the specified string, the
infomation will be stored (example: RUBY_DEBUG_LOG_FILTER=str will enable
only on str related information).

In a MRI source code, you can use the following macros:
  * RUBY_DEBUG_LOG(fmt, ...): Above (1) to (4) will be logged.
  * RUBY_DEBUG_LOG2(file, line, fmt, ...):
    Same as RUBY_DEBUG_LOG(), but (1) will be replaced with given file, line.

1 files changed, 1 insertions, 0 deletions

diff --git a/.github/workflows/compilers.yml b/.github/workflows/compilers.yml
index 6925477aaf..5e58de225f 100644
--- a/.github/workflows/compilers.yml
+++ b/.github/workflows/compilers.yml
@@ -116,6 +116,7 @@ jobs:
           - { key: cppflags, name: USE_SYMBOL_GC=0,                value: '-DUSE_SYMBOL_GC=0' }
           - { key: cppflags, name: USE_THREAD_CACHE=0,             value: '-DUSE_THREAD_CACHE=0' }
           - { key: cppflags, name: USE_TRANSIENT_HEAP=0,           value: '-DUSE_TRANSIENT_HEAP=0' }
+          - { key: cppflags, name: USE_RUBY_DEBUG_LOG=1,           value: '-DUSE_RUBY_DEBUG_LOG=1' }
 
           - { key: cppflags, name: DEBUG_FIND_TIME_NUMGESS,        value: '-DDEBUG_FIND_TIME_NUMGESS' }
           - { key: cppflags, name: DEBUG_INTEGER_PACK,             value: '-DDEBUG_INTEGER_PACK' }