windows: clarify the need for invalidcontinue.obj

dscho · dscho · commit 21811292582d · 2017-02-03T07:19:29.000+01:00
Git's source code wants to be able to close() the same file descriptor multiple times, ignoring the error returned by the second call (and the ones after that), or to access the osfhandle of an already-closed stdout, among other things that the UCRT does not like. Simply linking invalidcontinue.obj allows such usage without resorting to Debug Assertions (or exiting with exit code 9 in Release Mode). Let's add a note so we don't forget, as suggested by Jeff Hostetler. See https://msdn.microsoft.com/en-us/library/ms235330.aspx for more details. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
diff --git a/config.mak.uname b/config.mak.uname
@@ -395,6 +395,9 @@ ifeq ($(uname_S),Windows)
 		compat/win32/dirent.o compat/win32/fscache.o
 	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
 	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -SUBSYSTEM:CONSOLE
+	# invalidcontinue.obj allows Git's source code to close the same file
+	# handle twice, or to access the osfhandle of an already-closed stdout
+	# See https://msdn.microsoft.com/en-us/library/ms235330.aspx
 	EXTLIBS = user32.lib advapi32.lib shell32.lib wininet.lib ws2_32.lib invalidcontinue.obj kernel32.lib ntdll.lib
 	PTHREAD_LIBS =
 	lib =
