subprocess-win32: add hint on ERROR_INVALID_PARAMETER

This is generally associated with the command line being too long. Give
a hint to this case in the error message.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/subprocess-win32.cc b/src/subprocess-win32.cc
index 5982b06..a4a7669 100644
--- a/src/subprocess-win32.cc
+++ b/src/subprocess-win32.cc
@@ -124,6 +124,10 @@ bool Subprocess::Start(SubprocessSet* set, const string& command) {
       buf_ = "CreateProcess failed: The system cannot find the file "
           "specified.\n";
       return true;
+    } else if (error == ERROR_INVALID_PARAMETER) {
+      // This generally means that the command line was too long. Give extra
+      // context for this case.
+      Win32Fatal("CreateProcess", "is the command line too long?");
     } else {
       Win32Fatal("CreateProcess");    // pass all other errors to Win32Fatal
     }