diff --git a/lib/preprocessor.cpp b/lib/preprocessor.cpp
index 3cad39045..01a8568a8 100644
--- a/lib/preprocessor.cpp
+++ b/lib/preprocessor.cpp
@@ -371,6 +371,8 @@ static void getConfigs(const simplecpp::TokenList &tokens, std::set<std::string>
                 configs_ifndef.pop_back();
         } else if (cmdtok->str == "error") {
             if (!configs_ifndef.empty() && !configs_ifndef.back().empty()) {
+                if (configs_ifndef.size() == 1U)
+                    ret.erase("");
                 std::vector<std::string> configs(configs_if);
                 configs.push_back(configs_ifndef.back());
                 ret.insert(cfg(configs, userDefines));
@@ -379,8 +381,11 @@ static void getConfigs(const simplecpp::TokenList &tokens, std::set<std::string>
                 const std::string &last = configs_if.back();
                 if (last.size() > 2U && last.compare(last.size()-2U,2,"=0") == 0) {
                     std::vector<std::string> configs(configs_if);
+                    ret.erase(cfg(configs, userDefines));
                     configs[configs.size() - 1U] = last.substr(0,last.size()-2U);
                     ret.insert(cfg(configs, userDefines));
+                    if (configs.size() == 1U)
+                        ret.erase("");
                 }
             }
         } else if (cmdtok->str == "define" && sameline(tok, cmdtok->next) && cmdtok->next->name) {
diff --git a/test/testpreprocessor.cpp b/test/testpreprocessor.cpp
index 40a541570..8a834e769 100644
--- a/test/testpreprocessor.cpp
+++ b/test/testpreprocessor.cpp
@@ -324,12 +324,12 @@ private:
         const char filedata1[] = "#ifndef A\n"
                                  "#error\n"
                                  "#endif\n";
-        TODO_ASSERT_EQUALS("A\n", "\nA\n", getConfigsStr(filedata1));
+        ASSERT_EQUALS("A\n", getConfigsStr(filedata1));
 
         const char filedata2[] = "#if !A\n"
                                  "#error\n"
                                  "#endif\n";
-        TODO_ASSERT_EQUALS("A\n", "\nA\nA=0\n", getConfigsStr(filedata2));
+        ASSERT_EQUALS("A\n", getConfigsStr(filedata2));
     }
 
     void error3() {
@@ -2098,7 +2098,7 @@ private:
         const char filedata1[] = "#ifndef X\n"
                                  "#error \"!X\"\n"
                                  "#endif\n";
-        ASSERT_EQUALS("\nX\n", getConfigsStr(filedata1));
+        ASSERT_EQUALS("X\n", getConfigsStr(filedata1));
 
         const char filedata2[] = "#ifdef X\n"
                                  "#ifndef Y\n"