fputc, fwrite tests: Avoid test failure on MSVC. * tests/test-fgetc.c: Include msvc-inval.h. (main): Invoke gl_msvc_inval_ensure_handler. * tests/test-fputc.c: Include msvc-inval.h. (main): Invoke gl_msvc_inval_ensure_handler. * tests/test-fread.c: Include msvc-inval.h. (main): Invoke gl_msvc_inval_ensure_handler. * tests/test-fwrite.c: Include msvc-inval.h. (main): Invoke gl_msvc_inval_ensure_handler. * modules/fgetc-tests (Depends-on): Add msvc-inval. * modules/fputc-tests (Depends-on): Likewise. * modules/fread-tests (Depends-on): Likewise. * modules/fwrite-tests (Depends-on): Likewise.

--- a/tests/test-fread.c
+++ b/tests/test-fread.c
@@ -26,6 +26,8 @@
 #include <fcntl.h>
 #include <unistd.h>
 
+#include "msvc-inval.h"
+
 #include "macros.h"
 
 int
@@ -33,6 +35,12 @@
 {
   const char *filename = "test-fread.txt";
 
+  /* We don't have an fread() function that installs an invalid parameter
+     handler so far.  So install that handler here, explicitly.  */
+#if MSVC_INVALID_PARAMETER_HANDLING == DEFAULT_HANDLING
+  gl_msvc_inval_ensure_handler ();
+#endif
+
   /* Prepare a file.  */
   {
     const char text[] = "hello world";