From 8ff97f621066747445e00911a965dc1933126e9e Mon Sep 17 00:00:00 2001
From: chao an <anchao@lixiang.com>
Date: Wed, 31 Jan 2024 09:02:08 +0800
Subject: [PATCH] compiler/tasking: fix unreachable code on tasking toolchain

ctc W544: ["serial/serial.c" 284/3] unreachable code
ctc W544: ["vfs/fs_lseek.c" 96/13] unreachable code
ctc W544: ["wqueue/kwork_thread.c" 210/32] unreachable code
ctc W544: ["stdio/lib_fopen.c" 327/19] unreachable code
ctc W544: ["stdio/lib_fopen.c" 404/13] unreachable code
ctc W544: ["string/lib_strcasestr.c" 120/3] unreachable code
ctc W544: ["unistd/lib_getopt_common.c" 156/21] unreachable code
ctc W544: ["unistd/lib_getopt_common.c" 216/21] unreachable code
ctc W544: ["wctype/lib_iswctype.c" 155/3] unreachable code

Signed-off-by: chao an <anchao@lixiang.com>
---
 drivers/serial/serial.c              |  2 +-
 fs/vfs/fs_lseek.c                    | 10 ++++------
 libs/libc/stdio/lib_fopen.c          |  2 --
 libs/libc/string/lib_strcasestr.c    |  2 +-
 libs/libc/unistd/lib_getopt_common.c |  2 --
 libs/libc/wctype/lib_iswctype.c      |  2 +-
 6 files changed, 7 insertions(+), 13 deletions(-)

diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index 43a4552796..ffce0f9bee 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -181,7 +181,7 @@ static int uart_putxmitchar(FAR uart_dev_t *dev, int ch, bool oktoblock)
 
           dev->xmit.buffer[dev->xmit.head] = ch;
           dev->xmit.head = nexthead;
-          return OK;
+          break;
         }
 
       /* The TX buffer is full.  Should be block, waiting for the hardware
diff --git a/fs/vfs/fs_lseek.c b/fs/vfs/fs_lseek.c
index 18c57e00b5..3bae28992e 100644
--- a/fs/vfs/fs_lseek.c
+++ b/fs/vfs/fs_lseek.c
@@ -84,15 +84,13 @@ off_t file_seek(FAR struct file *filep, off_t offset, int whence)
             /* FALLTHROUGH */
 
           case SEEK_SET:
-            if (offset >= 0)
-              {
-                filep->f_pos = offset; /* Might be beyond the end-of-file */
-                break;
-              }
-            else
+            if (offset < 0)
               {
                 return -EINVAL;
               }
+
+            filep->f_pos = offset; /* Might be beyond the end-of-file */
+
             break;
 
           case SEEK_END:
diff --git a/libs/libc/stdio/lib_fopen.c b/libs/libc/stdio/lib_fopen.c
index d446e0960c..50293282db 100644
--- a/libs/libc/stdio/lib_fopen.c
+++ b/libs/libc/stdio/lib_fopen.c
@@ -324,7 +324,6 @@ int lib_mode2oflags(FAR const char *mode)
 
                 default:
                   goto errout;
-                  break;
               }
             break;
 
@@ -401,7 +400,6 @@ int lib_mode2oflags(FAR const char *mode)
 
           default:
             goto errout;
-            break;
         }
     }
 
diff --git a/libs/libc/string/lib_strcasestr.c b/libs/libc/string/lib_strcasestr.c
index 369044253d..9ccddaff16 100644
--- a/libs/libc/string/lib_strcasestr.c
+++ b/libs/libc/string/lib_strcasestr.c
@@ -92,7 +92,7 @@ FAR char *strcasestr(FAR const char *str, FAR const char *substr)
            * substring.
            */
 
-          return NULL;
+          break;
         }
 
       /* Check if this is the beginning of a matching substring
diff --git a/libs/libc/unistd/lib_getopt_common.c b/libs/libc/unistd/lib_getopt_common.c
index be3e22a21a..cede600c67 100644
--- a/libs/libc/unistd/lib_getopt_common.c
+++ b/libs/libc/unistd/lib_getopt_common.c
@@ -153,7 +153,6 @@ static int getopt_long_option(FAR struct getopt_s *go,
 
                   default:
                     goto errout;
-                    break;
                 }
             }
           else
@@ -213,7 +212,6 @@ static int getopt_long_option(FAR struct getopt_s *go,
 
                   default:
                     goto errout;
-                    break;
                 }
             }
 
diff --git a/libs/libc/wctype/lib_iswctype.c b/libs/libc/wctype/lib_iswctype.c
index 235b8e18ec..034ea9b799 100644
--- a/libs/libc/wctype/lib_iswctype.c
+++ b/libs/libc/wctype/lib_iswctype.c
@@ -147,7 +147,7 @@ int iswctype(wint_t c, wctype_t desc)
       return iswxdigit(c);
 
     default:
-      return 0;                 /* eliminate warning */
+      break;                 /* eliminate warning */
     }
 
   /* Otherwise unknown */