bootstrap: Require compiler mode aware of C++11

Some compilers have enough features enabled in their default modes to
pass our simple C++11 unique_ptr check but do not enable enough to build
CMake.  Poison this case so that we choose one of the explicit `-std=`
options for such compilers.

1 files changed, 6 insertions, 2 deletions

diff --git a/bootstrap b/bootstrap
index e543d62..430f53b 100755
--- a/bootstrap
+++ b/bootstrap
@@ -988,8 +988,12 @@ echo '
 #include <iostream>
 #include <memory>
 
-#if __cplusplus >= 201103L && defined(__SUNPRO_CC) && __SUNPRO_CC < 0x5140
-#error "SunPro <= 5.13 C++ 11 mode not supported due to bug in move semantics."
+#if __cplusplus < 201103L
+#error "Compiler is not in a mode aware of C++11."
+#endif
+
+#if defined(__SUNPRO_CC) && __SUNPRO_CC < 0x5140
+#error "SunPro <= 5.13 mode not supported due to bug in move semantics."
 #endif
 
 class Class