BUG, DIST: Print os error message when the executable not exist

  this patch is really important since most of the users aren't able to determine
  the build error when the toolchain or the built environment missing
  executable files of compiler, linker, assembler, etc.

Author: seiko2plus

numpy/distutils/ccompiler.py

@@ -144,12 +144,18 @@ def CCompiler_spawn(self, cmd, display=None):
     except subprocess.CalledProcessError as exc:
         o = exc.output
         s = exc.returncode
-    except OSError:
+    except OSError as e:
         # OSError doesn't have the same hooks for the exception
         # output, but exec_command() historically would use an
         # empty string for EnvironmentError (base class for
         # OSError)
-        o = b''
+        # o = b''
+        # still that would make the end-user lost in translation!
+        o = f"\n\n{e}\n\n\n"
+        try:
+            o = o.encode(sys.stdout.encoding)
+        except AttributeError:
+            o = o.encode('utf8')
         # status previously used by exec_command() for parent
         # of OSError
         s = 127

numpy/distutils/ccompiler_opt.py

@@ -721,8 +721,8 @@ def _dist_test_spawn(cmd, display=None):
         except subprocess.CalledProcessError as exc:
             o = exc.output
             s = exc.returncode
-        except OSError:
-            o = b''
+        except OSError as e:
+            o = e
             s = 127
         else:
             return None