From: Michał Kępień <michal@isc.org>
Date: Mon, 18 May 2020 08:23:06 +0000 (+0200)
Subject: Work around cppcheck 2.0 uninitvar false positives
X-Git-Tag: v9.17.2~70^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=481fa34e50a6183273f71175adf93bfb12cad1e9;p=thirdparty%2Fbind9.git

Work around cppcheck 2.0 uninitvar false positives

cppcheck 2.0 reports false positives about uninitialized variables in a
lot of places throughout BIND source code, e.g.:

    bin/dnssec/dnssec-cds.c:283:6: error: Uninitialized variable: length [uninitvar]
     if (isc_buffer_availablelength(&buf) <= len) {
         ^

Apparently cppcheck 2.0 has issues with processing (&var)->field syntax,
which is what the macros from lib/isc/include/isc/buffer.h are evaluated
to.  This issue was reported upstream [1] and will hopefully be
addressed in a future cppcheck release.

In the meantime, to avoid modifying BIND source code in multiple places
just because of a static checker false positive, work around the issue
by adding intermediate variables to buffer macro definitions using a sed
invocation in the cppcheck job script.

[1] https://sourceforge.net/p/cppcheck/discussion/general/thread/122153e3c1/
---

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index de72ea5a904..3f47a8262b4 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -353,6 +353,9 @@ stages:
   <<: *default_triggering_rules
   stage: postcheck
   script:
+    # Workaround for cppcheck 2.0 uninitvar false positives triggered by (&var)->field syntax
+    # (see: https://sourceforge.net/p/cppcheck/discussion/general/thread/122153e3c1/)
+    - sed -i '/^#define ISC__BUFFER.*\\$/{s|_b|__b|;N;s|do {|\0 isc_buffer_t *_b = (isc_buffer_t *)__b;|}; /^#define ISC__BUFFER.*REGION.*\\$/{s|_r|__r|;N;s|do {|\0 isc_region_t *_r = (isc_region_t *)__r;|; /USEDREGION/{s|isc_buffer_t|const \0|g}}' lib/isc/include/isc/buffer.h
     - *configure
     - (make -nwk all || true) | compiledb
     - export GCC_VERSION=$(gcc --version | sed -n 's/.* \([0-9]\+\)\.[0-9]\+\.[0-9]\+.*/\1/p')