Merge pull request #688 from github/michaelrfairhurst/fix-autosar-a1-1-2-on-gcc-detect-suppress-warning-flag

Detect compilations with no warnings when '-w' flag is present.

Author: lcartey

change_notes/2024-9-20-a1-1-2-improvements.md

@@ -0,0 +1,2 @@
+- `A1-1-2` - `CompilerWarningLevelNotInCompliance.ql`:
+    - Report non-compliance for compilations that use the error-suppressing `-w` flag.

cpp/autosar/src/rules/A1-1-2/CompilerWarningLevelNotInCompliance.ql

@@ -18,15 +18,17 @@
 import cpp
 import codingstandards.cpp.autosar
 
-predicate hasResponseFileArgument(Compilation c) { c.getAnArgument().matches("@%") }
+class CompilationWithNoWarnings extends Compilation {
+  CompilationWithNoWarnings() {
+    getAnArgument() = "-w" or
+    not getAnArgument().regexpMatch("-W[\\w=-]+")
+  }
+}
 
-predicate hasWarningOption(Compilation c) { c.getAnArgument().regexpMatch("-W[\\w=-]+") }
+predicate hasResponseFileArgument(Compilation c) { c.getAnArgument().matches("@%") }
 
 from File f
 where
   not isExcluded(f, ToolchainPackage::compilerWarningLevelNotInComplianceQuery()) and
-  exists(Compilation c | f = c.getAFileCompiled() |
-    not hasResponseFileArgument(c) and
-    not hasWarningOption(c)
-  )
+  exists(CompilationWithNoWarnings c | f = c.getAFileCompiled() | not hasResponseFileArgument(c))
 select f, "No warning-level options were used in the compilation of '" + f.getBaseName() + "'."

cpp/autosar/test/rules/A1-1-2.2/CompilerWarningLevelNotInCompliance.expected

@@ -0,0 +1 @@
+| Wcast-function-type.cpp:0:0:0:0 | Wcast-function-type.cpp | No warning-level options were used in the compilation of 'Wcast-function-type.cpp'. |

cpp/autosar/test/rules/A1-1-2.2/CompilerWarningLevelNotInCompliance.expected.clang

@@ -1,2 +1,14 @@
 // semmle-extractor-options: --clang -std=c++14 -Wcast-function-type
-// COMPLIANT
+// COMPLIANT
+
+// NOTE: When tested with `codeql test run`, the test extractor provides `-w`
+// which overrides `-Wcast-function-type` and causes this test case to be
+// non-compliant.
+//
+// However, when tested with our compiler matrix tests, this test db is built
+// via `codeql database create --command="..."`, and the `-w` flag will NOT be
+// used. This means the `-Wcast-function-type` flag is active and the test case
+// is compliant.
+//
+// Therefore, the .expected file for this test expects non-compliance, and the
+// .expected.gcc and .expected.clang files expect this test to be compliant.

cpp/autosar/test/rules/A1-1-2.2/CompilerWarningLevelNotInCompliance.expected.gcc

@@ -0,0 +1 @@
+| Wall.cpp:0:0:0:0 | Wall.cpp | No warning-level options were used in the compilation of 'Wall.cpp'. |