Fix 8124: False positive va_end missing with lambda (cppcheck-opensource#1577)

rikardfalkeborn · danmar · commit a48c8abcda5e · 2019-01-10T18:32:17.000+01:00
Skip lambdas, to avoid false positives due to possible
return statements in lambdas.

Also, run dmake.
diff --git a/Makefile b/Makefile
@@ -430,7 +430,7 @@ $(SRCDIR)/checkunusedfunctions.o: lib/checkunusedfunctions.cpp lib/checkunusedfu
 $(SRCDIR)/checkunusedvar.o: lib/checkunusedvar.cpp lib/checkunusedvar.h lib/check.h lib/config.h lib/errorlogger.h lib/suppressions.h lib/settings.h lib/importproject.h lib/platform.h lib/utils.h lib/library.h lib/mathlib.h lib/standards.h lib/timer.h lib/token.h lib/valueflow.h lib/templatesimplifier.h lib/tokenize.h lib/tokenlist.h lib/astutils.h lib/symboldatabase.h
 	$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CFG) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(SRCDIR)/checkunusedvar.o $(SRCDIR)/checkunusedvar.cpp
 
-$(SRCDIR)/checkvaarg.o: lib/checkvaarg.cpp lib/checkvaarg.h lib/check.h lib/config.h lib/errorlogger.h lib/suppressions.h lib/settings.h lib/importproject.h lib/platform.h lib/utils.h lib/library.h lib/mathlib.h lib/standards.h lib/timer.h lib/token.h lib/valueflow.h lib/templatesimplifier.h lib/tokenize.h lib/tokenlist.h lib/symboldatabase.h
+$(SRCDIR)/checkvaarg.o: lib/checkvaarg.cpp lib/checkvaarg.h lib/check.h lib/config.h lib/errorlogger.h lib/suppressions.h lib/settings.h lib/importproject.h lib/platform.h lib/utils.h lib/library.h lib/mathlib.h lib/standards.h lib/timer.h lib/token.h lib/valueflow.h lib/templatesimplifier.h lib/tokenize.h lib/tokenlist.h lib/astutils.h lib/symboldatabase.h
 	$(CXX) ${INCLUDE_FOR_LIB} $(CPPFLAGS) $(CFG) $(CXXFLAGS) $(UNDEF_STRICT_ANSI) -c -o $(SRCDIR)/checkvaarg.o $(SRCDIR)/checkvaarg.cpp
 
 $(SRCDIR)/cppcheck.o: lib/cppcheck.cpp lib/cppcheck.h lib/analyzerinfo.h lib/config.h lib/errorlogger.h lib/suppressions.h lib/importproject.h lib/platform.h lib/utils.h lib/check.h lib/settings.h lib/library.h lib/mathlib.h lib/standards.h lib/timer.h lib/token.h lib/valueflow.h lib/templatesimplifier.h lib/tokenize.h lib/tokenlist.h lib/checkunusedfunctions.h lib/ctu.h lib/path.h lib/preprocessor.h lib/version.h
diff --git a/lib/checkvaarg.cpp b/lib/checkvaarg.cpp
@@ -18,6 +18,7 @@
 
 #include "checkvaarg.h"
 
+#include "astutils.h"
 #include "errorlogger.h"
 #include "settings.h"
 #include "symboldatabase.h"
@@ -107,6 +108,10 @@ void CheckVaarg::va_list_usage()
 
         const Token* tok = var->nameToken()->next();
         for (;  tok && tok != var->scope()->bodyEnd; tok = tok->next()) {
+            // Skip lambdas
+            const Token* tok2 = findLambdaEndToken(tok);
+            if (tok2)
+                tok = tok2;
             if (Token::Match(tok, "va_start ( %varid%", var->declarationId())) {
                 if (open)
                     va_start_subsequentCallsError(tok, var->name());
diff --git a/test/testvaarg.cpp b/test/testvaarg.cpp
@@ -155,6 +155,32 @@ class TestVaarg : public TestFixture {
               "    va_end(arg_ptr);\n"
               "}");
         ASSERT_EQUALS("[test.cpp:4]: (error) va_list 'arg_ptr' was opened but not closed by va_end().\n", errout.str());
+
+        // #8124
+        check("void f(int n, ...)\n"
+              "{\n"
+              "    va_list ap;\n"
+              "    va_start(ap, n);\n"
+              "    std::vector<std::string> v(n);\n"
+              "    std::generate_n(v.begin(), n, [&ap]()\n"
+              "    {\n"
+              "        return va_arg(ap, const char*);\n"
+              "    });\n"
+              "    va_end(ap);\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+
+        check("void f(int n, ...)\n"
+              "{\n"
+              "    va_list ap;\n"
+              "    va_start(ap, n);\n"
+              "    std::vector<std::string> v(n);\n"
+              "    std::generate_n(v.begin(), n, [&ap]()\n"
+              "    {\n"
+              "        return va_arg(ap, const char*);\n"
+              "    });\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:10]: (error) va_list 'ap' was opened but not closed by va_end().\n", errout.str());
     }
 
     void va_list_usedBeforeStarted() {
