From: Matthias Köppe <mkoeppe@math.ucdavis.edu>
Date: Mon, 20 Jun 2022 13:58:02 +0000 (-0400)
Subject: gh-90539: doc: Expand on what should not go into CFLAGS, LDFLAGS (#92754)
X-Git-Tag: v3.12.0a1~1194
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=61f24e7885bed096b5d7f75aff13c1001994b35a;p=thirdparty%2FPython%2Fcpython.git

gh-90539: doc: Expand on what should not go into CFLAGS, LDFLAGS (#92754)
---

diff --git a/Doc/using/configure.rst b/Doc/using/configure.rst
index 8cbeb496f2df..80c0dc08dae7 100644
--- a/Doc/using/configure.rst
+++ b/Doc/using/configure.rst
@@ -749,6 +749,17 @@ Compiler flags
    extensions.  Use it when a compiler flag should *not* be part of the
    distutils :envvar:`CFLAGS` once Python is installed (:issue:`21121`).
 
+   In particular, :envvar:`CFLAGS` should not contain:
+
+   * the compiler flag `-I` (for setting the search path for include files).
+     The `-I` flags are processed from left to right, and any flags in
+     :envvar:`CFLAGS` would take precedence over user- and package-supplied `-I`
+     flags.
+
+   * hardening flags such as `-Werror` because distributions cannot control
+     whether packages installed by users conform to such heightened
+     standards.
+
    .. versionadded:: 3.5
 
 .. envvar:: EXTRA_CFLAGS
@@ -861,6 +872,13 @@ Linker flags
    :envvar:`CFLAGS_NODIST`.  Use it when a linker flag should *not* be part of
    the distutils :envvar:`LDFLAGS` once Python is installed (:issue:`35257`).
 
+   In particular, :envvar:`LDFLAGS` should not contain:
+
+   * the compiler flag `-L` (for setting the search path for libraries).
+     The `-L` flags are processed from left to right, and any flags in
+     :envvar:`LDFLAGS` would take precedence over user- and package-supplied `-L`
+     flags.
+
 .. envvar:: CONFIGURE_LDFLAGS_NODIST
 
    Value of :envvar:`LDFLAGS_NODIST` variable passed to the ``./configure``