TIL: Explicit case fallthrough

perlun · perlun · commit 2f2b6e8ced1f · 2017-09-27T00:30:32.000+03:00
More details: https://developers.redhat.com/blog/2017/03/10/wimplicit-fallthrough-in-gcc-7/
diff --git a/libraries/string/string.c b/libraries/string/string.c
@@ -538,6 +538,8 @@ return_type string_print_va(char *output, const char *format_string,
                     case 'X':
                     {
                         flags |= UPPER_HEX;
+
+                        // Falls through by design. (Can't use __attribute__ ((fallthrough)), since it breaks on gcc < 7.)
                     }
 
                     case 'x':

Original file line number	Diff line number	Diff line change
`@@ -538,6 +538,8 @@ return_type string_print_va(char output, const char format_string,`
`538`	`538`	`case 'X':`
`539`	`539`	`{`
`540`	`540`	`flags \|= UPPER_HEX;`
	`541`	`+`
	`542`	`+ // Falls through by design. (Can't use __attribute__ ((fallthrough)), since it breaks on gcc < 7.)`
`541`	`543`	`}`
`542`	`544`
`543`	`545`	`case 'x':`