Disable -Wimplicit-fallthrough for these two files.

These two files contain code with multiple switch statements,
where one case "fall through" to the next case.
As it's not currently clear if this is intentional or not,
rather than modifying the code in any way (regression risk),
use GCC diagnostic pragmas to disable this warning for
only these two files, with BUGBUG marking to encourage
review by someone more familiar with this code.

Author: henrygab

libraries/USBHost/src/confdescparser.h

@@ -19,6 +19,17 @@ e-mail   :  [email protected]
 #error "Never include confdescparser.h directly; include Usb.h instead"
 #else
 
+#pragma GCC diagnostic push // Available since GCC 4.6.4
+/*
+ * BUGBUG -- Enabled and review all `-Wimplicit-fallthrough` messages
+ * This code has multiple switch statements that "fall through" to the
+ * next case -- but it's not always clear if this is intentional or not.
+ * Review and commenting of code, and reducing cyclomatic complexity
+ * are highly recommended....
+ */
+#pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
+
+
 #define __CONFDESCPARSER_H__
 
 #include <stdint.h>
@@ -220,4 +231,6 @@ void ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::PrintHidDescrip
 }
 
 
+#pragma GCC diagnostic pop
+
 #endif // __CONFDESCPARSER_H__

libraries/USBHost/src/parsetools.h

@@ -23,6 +23,19 @@ e-mail   :  [email protected]
 #include <stdint.h>
 //#include "Arduino.h"
 
+#pragma GCC diagnostic push // Available since GCC 4.6.4
+/*
+ * BUGBUG -- Enabled and review all `-Wimplicit-fallthrough` messages
+ * This code has multiple switch statements that "fall through" to the
+ * next case -- but it's not always clear if this is intentional or not.
+ * Review and commenting of code, and reducing cyclomatic complexity
+ * are highly recommended....
+ */
+#pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
+
+
+
+
 struct MultiValueBuffer {
 	uint8_t		valueSize;
 	void		*pValue;
@@ -140,4 +153,7 @@ class PTPListParser {
 	bool Parse(uint8_t **pp, uint32_t *pcntdn, PTP_ARRAY_EL_FUNC pf, const void *me = NULL);
 };
 
+
+#pragma GCC diagnostic pop
+
 #endif // __PARSETOOLS_H__