Updated 'noValidConfiguration' message. It should not write this message when there is no code. It should be possible to see the preprocessor errors otherwise it is hard to fix the configuration.

lib/cppcheck.cpp

@@ -304,6 +304,7 @@ unsigned int CppCheck::checkFile(const std::string& filename, const std::string
         std::set<unsigned long long> checksums;
         unsigned int checkCount = 0;
         bool hasValidConfig = false;
+        std::list<std::string> configurationError;
         for (std::set<std::string>::const_iterator it = configurations.begin(); it != configurations.end(); ++it) {
             // bail out if terminated
             if (_settings.terminated())
@@ -361,9 +362,9 @@ unsigned int CppCheck::checkFile(const std::string& filename, const std::string
                 const simplecpp::TokenList &tokensP = preprocessor.preprocess(tokens1, cfg, files);
                 _tokenizer.createTokens(&tokensP);
                 timer.Stop();
+                hasValidConfig = true;
                 if (tokensP.empty())
                     continue;
-                hasValidConfig = true;
 
                 // skip rest of iteration if just checking configuration
                 if (_settings.checkConfiguration)
@@ -418,6 +419,12 @@ unsigned int CppCheck::checkFile(const std::string& filename, const std::string
                     checkSimplifiedTokens(_tokenizer);
                 }
 
+            } catch (const simplecpp::Output &o) {
+                // #error etc during preprocessing
+                configurationError.push_back(std::string(o.location.file() + ':' + MathLib::toString(o.location.line) + ": " + o.msg));
+                --checkCount; // don't count invalid configurations
+                continue;
+
             } catch (const InternalError &e) {
                 internalErrorFound=true;
                 std::list<ErrorLogger::ErrorMessage::FileLocation> locationList;
@@ -445,6 +452,12 @@ unsigned int CppCheck::checkFile(const std::string& filename, const std::string
         }
 
         if (!hasValidConfig && configurations.size() > 1 && _settings.isEnabled(Settings::INFORMATION)) {
+            std::string msg;
+            msg = "This file is not analyzed. Every tested configuration results in preprocessor errors. It seems that Cppcheck failed to extract a valid configuration. Use -v for more details.";
+            msg += "\nThis file is not analyzed. Every tested configuration results in preprocessor errors. It seems that Cppcheck failed to extract a valid configuration. The preprocessor errors:";
+            for (const std::string &s : configurationError)
+                msg += "\n  " + s;
+
             std::list<ErrorLogger::ErrorMessage::FileLocation> locationList;
             ErrorLogger::ErrorMessage::FileLocation loc;
             loc.setfile(Path::toNativeSeparators(filename));
@@ -452,7 +465,7 @@ unsigned int CppCheck::checkFile(const std::string& filename, const std::string
             ErrorLogger::ErrorMessage errmsg(locationList,
                                              loc.getfile(),
                                              Severity::information,
-                                             "No tested configuration is valid, this file is not analyzed.",
+                                             msg,
                                              "noValidConfiguration",
                                              false);
             reportErr(errmsg);

lib/preprocessor.cpp

@@ -619,8 +619,21 @@ simplecpp::TokenList Preprocessor::preprocess(const simplecpp::TokenList &tokens
 
     const bool showerror = (!_settings.userDefines.empty() && !_settings.force);
     reportOutput(outputList, showerror);
-    if (hasErrors(outputList))
+    if (hasErrors(outputList)) {
-        return simplecpp::TokenList(files);
+        for (const simplecpp::Output &output : outputList) {
+            switch (output.type) {
+            case simplecpp::Output::ERROR:
+            case simplecpp::Output::INCLUDE_NESTED_TOO_DEEPLY:
+            case simplecpp::Output::SYNTAX_ERROR:
+            case simplecpp::Output::UNHANDLED_CHAR_ERROR:
+                throw output;
+            case simplecpp::Output::WARNING:
+            case simplecpp::Output::MISSING_HEADER:
+            case simplecpp::Output::PORTABILITY_BACKSLASH:
+                break;
+            };
+        }
+    }
 
     tokens2.removeComments();
 
@@ -675,7 +688,13 @@ std::string Preprocessor::getcode(const std::string &filedata, const std::string
     if (hasErrors(outputList))
         return "";
 
-    return getcode(tokens1, cfg, files, filedata.find("#file") != std::string::npos);
+    std::string ret;
+    try {
+        ret = getcode(tokens1, cfg, files, filedata.find("#file") != std::string::npos);
+    } catch (const simplecpp::Output &o) {
+        ret.clear();
+    }
+    return ret;
 }
 
 void Preprocessor::reportOutput(const simplecpp::OutputList &outputList, bool showerror)

test/testpreprocessor.cpp

@@ -262,6 +262,8 @@ private:
             try {
                 const std::string &cfgcode = preprocessor0.getcode(tokens, *it, files, std::string(code).find("#file") != std::string::npos);
                 actual[*it] = cfgcode;
+            } catch (const simplecpp::Output &o) {
+                actual[*it] = "";
             } catch (...) {
             }
         }