Clang on OpenBSD does not use GNU.

Author: nanolith

src/ansi-c/c_preprocess.cpp

@@ -589,19 +589,39 @@ bool c_preprocess_gcc_clang(
     switch(config.cpp.cpp_standard)
     {
     case configt::cppt::cpp_standardt::CPP98:
-      argv.push_back("-std=gnu++98");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c++98");
+      else
+    #endif
+        argv.push_back("-std=gnu++98");
       break;
 
     case configt::cppt::cpp_standardt::CPP03:
-      argv.push_back("-std=gnu++03");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c++03");
+      else
+    #endif
+        argv.push_back("-std=gnu++03");
       break;
 
     case configt::cppt::cpp_standardt::CPP11:
-      argv.push_back("-std=gnu++11");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c++11");
+      else
+    #endif
+        argv.push_back("-std=gnu++11");
       break;
 
     case configt::cppt::cpp_standardt::CPP14:
-      argv.push_back("-std=gnu++14");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c++14");
+      else
+    #endif
+        argv.push_back("-std=gnu++14");
       break;
     }
   }
@@ -610,15 +630,30 @@ bool c_preprocess_gcc_clang(
     switch(config.ansi_c.c_standard)
     {
     case configt::ansi_ct::c_standardt::C89:
-      argv.push_back("-std=gnu89");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c89");
+      else
+    #endif
+        argv.push_back("-std=gnu89");
       break;
 
     case configt::ansi_ct::c_standardt::C99:
-      argv.push_back("-std=gnu99");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c99");
+      else
+    #endif
+        argv.push_back("-std=gnu99");
       break;
 
     case configt::ansi_ct::c_standardt::C11:
-      argv.push_back("-std=gnu11");
+    #if defined(__OpenBSD__)
+      if (preprocessor==configt::ansi_ct::preprocessort::CLANG)
+        argv.push_back("-std=c11");
+      else
+    #endif
+        argv.push_back("-std=gnu11");
       break;
     }
   }

src/util/config.cpp

@@ -677,7 +677,7 @@ configt::ansi_ct::c_standardt configt::ansi_ct::default_c_standard()
   #if defined(__APPLE__)
   // By default, clang on the Mac builds C code in GNU C11
   return c_standardt::C11;
-  #elif defined(__FreeBSD__)
+  #elif defined(__FreeBSD__) || defined(__OpenBSD__)
   // By default, clang on FreeBSD builds C code in GNU C99
   return c_standardt::C99;
   #else