From: Michał Kępień <michal@isc.org>
Date: Wed, 16 Oct 2019 20:06:00 +0000 (+0200)
Subject: Fix cppcheck 1.89 warnings
X-Git-Tag: v9.15.6~57^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=abfde3d543576311ce5d32089d774a360b7edc9f;p=thirdparty%2Fbind9.git

Fix cppcheck 1.89 warnings

cppcheck 1.89 enabled certain value flow analysis mechanisms [1] which
trigger null pointer dereference false positives in lib/dns/rpz.c:

    lib/dns/rpz.c:582:7: warning: Possible null pointer dereference: tgt_ip [nullPointer]
      if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) {
          ^
    lib/dns/rpz.c:1419:44: note: Calling function 'adj_trigger_cnt', 4th argument 'NULL' value is 0
      adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, true);
                                               ^
    lib/dns/rpz.c:582:7: note: Null pointer dereference
      if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) {
          ^
    lib/dns/rpz.c:596:7: warning: Possible null pointer dereference: tgt_ip [nullPointer]
      if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) {
          ^
    lib/dns/rpz.c:1419:44: note: Calling function 'adj_trigger_cnt', 4th argument 'NULL' value is 0
      adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, true);
                                               ^
    lib/dns/rpz.c:596:7: note: Null pointer dereference
      if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) {
          ^
    lib/dns/rpz.c:610:7: warning: Possible null pointer dereference: tgt_ip [nullPointer]
      if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) {
          ^
    lib/dns/rpz.c:1419:44: note: Calling function 'adj_trigger_cnt', 4th argument 'NULL' value is 0
      adj_trigger_cnt(rpzs, rpz_num, rpz_type, NULL, 0, true);
                                               ^
    lib/dns/rpz.c:610:7: note: Null pointer dereference
      if (KEY_IS_IPV4(tgt_prefix, tgt_ip)) {
          ^

It seems that cppcheck no longer treats at least some REQUIRE()
assertion failures as fatal, so add extra assertion macro definitions to
lib/isc/include/isc/util.h that are only used when the CPPCHECK
preprocessor macro is defined; these definitions make cppcheck 1.89
behave as expected.

There is an important requirement for these custom definitions to work:
cppcheck must properly treat abort() as a function which does not
return.  In order for that to happen, the __GNUC__ macro must be set to
a high enough number (because system include directories are used and
system headers compile attributes away if __GNUC__ is not high enough).
__GNUC__ is thus set to the major version number of the GCC compiler
used, which is what that latter does itself during compilation.

[1] https://github.com/danmar/cppcheck/commit/aaeec462e6d96bb70c2b1cf030979d09e2d7c959
---

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 442f2d16cf0..5400d1bb852 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -256,6 +256,9 @@ stages:
 .cppcheck: &cppcheck_job
   <<: *default_triggering_rules
   stage: postcheck
+  before_script:
+    - export GCC_VERSION=$(gcc --version | sed -n 's/.*\([0-9]\+\)\.[0-9]\+\.[0-9]\+.*/\1/p')
+    - sed -i "/gcc\",/a\"-DCPPCHECK\", \"-D__STDC__\", \"-D__GNUC__=${GCC_VERSION}\"," compile_commands.json
   script:
     - *run_cppcheck
   after_script:
diff --git a/lib/isc/include/isc/util.h b/lib/isc/include/isc/util.h
index 730cfc268fc..9f65d629702 100644
--- a/lib/isc/include/isc/util.h
+++ b/lib/isc/include/isc/util.h
@@ -234,6 +234,9 @@ extern void mock_assert(const int result, const char* const expression,
 #define _assert_int_not_equal(a, b, f, l) \
 	(((a) != (b)) ? (void)0 : (_assert_int_not_equal(a, b, f, l), abort()))
 #else /* UNIT_TESTING */
+
+#ifndef CPPCHECK
+
 /*
  * Assertions
  */
@@ -248,6 +251,19 @@ extern void mock_assert(const int result, const char* const expression,
 /*% Invariant Assertion */
 #define INVARIANT(e)			ISC_INVARIANT(e)
 
+#else /* CPPCHECK */
+
+/*% Require Assertion */
+#define REQUIRE(e)			if (!(e)) abort()
+/*% Ensure Assertion */
+#define ENSURE(e)			if (!(e)) abort()
+/*% Insist Assertion */
+#define INSIST(e)			if (!(e)) abort()
+/*% Invariant Assertion */
+#define INVARIANT(e)			if (!(e)) abort()
+
+#endif /* CPPCHECK */
+
 #endif /* UNIT_TESTING */
 
 /*