[Python-checkins] bpo-42521: Add note about 'Python -d' only working on debug builds (GH-23607)

[miss-islington]

https://github.com/python/cpython/commit/9b34f34aa929941576a69a6f7de77f1fb0b96ed6
commit: 9b34f34aa929941576a69a6f7de77f1fb0b96ed6
branch: 3.9
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: miss-islington <31488909+miss-islington at users.noreply.github.com>
date: 2020-12-02T14:01:23-08:00
summary:

bpo-42521: Add note about 'Python -d' only working on debug builds (GH-23607)

(cherry picked from commit 99b594404d364b363c184f48338d6ee81bee26dd)

Co-authored-by: Pablo Galindo <Pablogsal at gmail.com>

files:
M Python/initconfig.c

diff --git a/Python/initconfig.c b/Python/initconfig.c
index e882a1fba5396..3caed385ef6af 100644
--- a/Python/initconfig.c
+++ b/Python/initconfig.c
@@ -42,7 +42,8 @@ Options and arguments (and corresponding environment variables):\n\
          and comparing bytes/bytearray with str. (-bb: issue errors)\n\
 -B     : don't write .pyc files on import; also PYTHONDONTWRITEBYTECODE=x\n\
 -c cmd : program passed in as string (terminates option list)\n\
--d     : debug output from parser; also PYTHONDEBUG=x\n\
+-d     : turn on parser debugging output (for experts only, only works on\n\
+         debug builds); also PYTHONDEBUG=x\n\
 -E     : ignore PYTHON* environment variables (such as PYTHONPATH)\n\
 -h     : print this help message and exit (also --help)\n\
 ";