Precompiled headers work for C++.

interpreter.py

@@ -484,7 +484,9 @@ class BuildTarget(InterpreterObject):
             elif environment.is_source(pchlist[0]):
                 if not environment.is_header(pchlist[1]):
                     raise InterpreterException('PCH definition must contain one header and at most one source.')
-            pchlist = [pchlist[1], pchlist[0]]
+                pchlist = [pchlist[1], pchlist[0]]
+            else:
+                raise InterpreterException('PCH argument %s is of unknown type.' % pchlist[0])
         elif len(pchlist) > 2:
             raise InterpreterException('PCH definition may have a maximum of 2 files.')
         self.pch[language] = pchlist

test cases/common/14 cpp pch/meson.build

@@ -1,2 +1,2 @@
 project('c++ pch test', 'cpp')
-exe = executable('prog', 'prog.cc', pch : 'pch/prog.hh')
+exe = executable('prog', 'prog.cc', cpp_pch : ['pch/prog.hh', 'pch/prog_pch.cc'])

test cases/common/14 cpp pch/pch/prog_pch.cc

@@ -0,0 +1,5 @@
+#if !defined(_MSC_VER)
+#error "This file is only for use with MSVC."
+#endif
+
+#include "prog.hh"