chelsio: use BUG() instead of BUG_ON(1)

arndb · davem330 · commit 047a013f8d0a · 2019-03-26T11:42:11.000-07:00
clang warns about possible bugs in a dead code branch after
BUG_ON(1) when CONFIG_PROFILE_ALL_BRANCHES is enabled:

 drivers/net/ethernet/chelsio/cxgb4/sge.c:479:3: error: variable 'buf_size' is used uninitialized whenever 'if'
      condition is false [-Werror,-Wsometimes-uninitialized]
                BUG_ON(1);
                ^~~~~~~~~
 include/asm-generic/bug.h:61:36: note: expanded from macro 'BUG_ON'
 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
                                   ^~~~~~~~~~~~~~~~~~~
 include/linux/compiler.h:48:23: note: expanded from macro 'unlikely'
 #  define unlikely(x)   (__branch_check__(x, 0, __builtin_constant_p(x)))
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 drivers/net/ethernet/chelsio/cxgb4/sge.c:482:9: note: uninitialized use occurs here
        return buf_size;
               ^~~~~~~~
 drivers/net/ethernet/chelsio/cxgb4/sge.c:479:3: note: remove the 'if' if its condition is always true
                BUG_ON(1);
                ^
 include/asm-generic/bug.h:61:32: note: expanded from macro 'BUG_ON'
 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
                               ^
 drivers/net/ethernet/chelsio/cxgb4/sge.c:459:14: note: initialize the variable 'buf_size' to silence this warning
        int buf_size;
                    ^
                     = 0

Use BUG() here to create simpler code that clang understands
correctly.

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
@@ -2620,7 +2620,7 @@ static inline struct port_info *ethqset2pinfo(struct adapter *adap, int qset)
 	}
 
 	/* should never happen! */
-	BUG_ON(1);
+	BUG();
 	return NULL;
 }
 
diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c
@@ -476,7 +476,7 @@ static inline int get_buf_size(struct adapter *adapter,
 		break;
 
 	default:
-		BUG_ON(1);
+		BUG();
 	}
 
 	return buf_size;

Original file line number	Diff line number	Diff line change
`@@ -2620,7 +2620,7 @@ static inline struct port_info ethqset2pinfo(struct adapter adap, int qset)`
`2620`	`2620`	`}`
`2621`	`2621`
`2622`	`2622`	`/* should never happen! */`
`2623`		`- BUG_ON(1);`
	`2623`	`+ BUG();`
`2624`	`2624`	`return NULL;`
`2625`	`2625`	`}`
`2626`	`2626`
Original file line number	Diff line number	Diff line change
`@@ -476,7 +476,7 @@ static inline int get_buf_size(struct adapter *adapter,`
`476`	`476`	`break;`
`477`	`477`
`478`	`478`	`default:`
`479`		`- BUG_ON(1);`
	`479`	`+ BUG();`
`480`	`480`	`}`
`481`	`481`
`482`	`482`	`return buf_size;`