[Stable-7.2.15,16/33] target/i386: Avoid unreachable variable declaration in mmu_translate()

Commit Message

Michael Tokarev Nov. 9, 2024, 6:38 a.m. UTC

From: Peter Maydell <[e-mail]>

Coverity complains (CID 1507880) that the declaration "int error_code;"
in mmu_translate() is unreachable code. Since this is only a declaration,
this isn't actually a bug, but:
 * it's a bear-trap for future changes, because if it was changed to
   include an initialization 'int error_code = foo;' then the
   initialization wouldn't actually happen (being dead code)
 * it's against our coding style, which wants declarations to be
   at the start of blocks
 * it means that anybody reading the code has to go and look up
   exactly what the C rules are for skipping over variable declarations
   using a goto

Move the declaration to the top of the function.

Signed-off-by: Peter Maydell <[e-mail]>
Message-Id: <[e-mail]>
Signed-off-by: Paolo Bonzini <[e-mail]>
(cherry picked from commit 987b63f24afe027a09b1c549c05a032a477f7e96)
Signed-off-by: Michael Tokarev <[e-mail]>
(Mjt: cherry-pick this for stable-7.2 so that the next patch applies cleanly)

Patch

diff --git a/target/i386/tcg/sysemu/excp_helper.c b/target/i386/tcg/sysemu/excp_helper.c
index 5f13252d68..eb78fcba11 100644
--- a/target/i386/tcg/sysemu/excp_helper.c
+++ b/target/i386/tcg/sysemu/excp_helper.c
@@ -146,6 +146,7 @@  static bool mmu_translate(CPUX86State *env, const TranslateParams *in,
     hwaddr pte_addr, paddr;
     uint32_t pkr;
     int page_size;
+    int error_code;
 
  restart_all:
     rsvd_mask = ~MAKE_64BIT_MASK(0, env_archcpu(env)->phys_bits);
@@ -464,7 +465,6 @@  do_check_protect_pse36:
     out->page_size = page_size;
     return true;
 
-    int error_code;
  do_fault_rsvd:
     error_code = PG_ERROR_RSVD_MASK;
     goto do_fault_cont;