[PATCH] scripts/kernel-doc: Override -Werror from KCFLAGS with KDOC_WERROR

From: Laurent Pinchart
Date: Fri Jul 30 2021 - 18:54:18 EST


Since commit 2c12c8103d8f ("scripts/kernel-doc: optionally treat
warnings as errors"), the kernel-doc script will treat warnings as
errors when one of the following conditions is true:

- The KDOC_WERROR environment variable is non-zero
- The KCFLAGS environment variable contains -Werror
- The -Werror parameter is passed to kernel-doc

Checking KCFLAGS for -Werror allows piggy-backing on the C compiler
error handling. However, unlike the C compiler, kernel-doc has no
provision for -Wno-error. This makes compiling the kernel with -Werror
(to catch regressions) and W=1 (to enable more checks) always fail,
without the same possibility as offered by the C compiler to treating
some selected warnings as warnings despite the global -Werror setting.

To fix this, evaluate KDOC_WERROR after KCFLAGS, which allows disabling
the warnings-as-errors behaviour of kernel-doc selectively by setting
KDOC_WERROR=0.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
scripts/kernel-doc | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index 7c4a6a507ac4..cfcb60737957 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -329,10 +329,6 @@ if (defined($ENV{'KBUILD_VERBOSE'})) {
$verbose = "$ENV{'KBUILD_VERBOSE'}";
}

-if (defined($ENV{'KDOC_WERROR'})) {
- $Werror = "$ENV{'KDOC_WERROR'}";
-}
-
if (defined($ENV{'KCFLAGS'})) {
my $kcflags = "$ENV{'KCFLAGS'}";

@@ -341,6 +337,10 @@ if (defined($ENV{'KCFLAGS'})) {
}
}

+if (defined($ENV{'KDOC_WERROR'})) {
+ $Werror = "$ENV{'KDOC_WERROR'}";
+}
+
# Generated docbook code is inserted in a template at a point where
# docbook v3.1 requires a non-zero sequence of RefEntry's; see:
# https://www.oasis-open.org/docbook/documentation/reference/html/refentry.html
--
Regards,

Laurent Pinchart