Remove redundant NULL tests.

GCC6 and Clang give warnings on redundant NULL tests of parameters
that are declared with __nonnull_attribute__.

Signed-off-by: Chih-Hung Hsieh <chh@google.com>
Signed-off-by: Mark Wielaard <mjw@redhat.com>

libdw/ChangeLog

@@ -1,3 +1,10 @@
+2015-09-09  Chih-Hung Hsieh  <chh@google.com>
+
+	* dwarf_macro_getsrcfiles.c (dwarf_macro_getsrcfiles): Remove
+	redundant NULL tests on parameters declared with __nonnull_attribute__.
+	* dwarf_siblingof.c (dwarf_siblingof): Likewise.
+	* libdw_visit_scopes.c (__libdw_visit_scopes): Likewise.
+
 2015-09-04  Chih-Hung Hsieh  <chh@google.com>
 	    Mark Wielaard  <mjw@redhat.com>
 

libdw/dwarf_macro_getsrcfiles.c

@@ -36,9 +36,7 @@ int
 dwarf_macro_getsrcfiles (Dwarf *dbg, Dwarf_Macro *macro,
 			 Dwarf_Files **files, size_t *nfiles)
 {
-  if (macro == NULL)
-    return -1;
-
+  /* macro is declared NN */
   Dwarf_Macro_Op_Table *const table = macro->table;
   if (table->files == NULL)
     {

libdw/dwarf_siblingof.c

@@ -45,8 +45,7 @@ dwarf_siblingof (die, result)
   if (die == NULL)
     return -1;
 
-  if (result == NULL)
-    return -1;
+  /* result is declared NN */
 
   if (result != die)
     result->addr = NULL;

libdw/libdw_visit_scopes.c

@@ -138,24 +138,22 @@ __libdw_visit_scopes (depth, root, imports, previsit, postvisit, arg)
 
 	child.prune = false;
 
-	if (previsit != NULL)
-	  {
-	    int result = (*previsit) (depth + 1, &child, arg);
-	    if (result != DWARF_CB_OK)
-	      return result;
-	  }
+	/* previsit is declared NN */
+	int result = (*previsit) (depth + 1, &child, arg);
+	if (result != DWARF_CB_OK)
+	  return result;
 
 	if (!child.prune && may_have_scopes (&child.die)
 	    && INTUSE(dwarf_haschildren) (&child.die))
 	  {
-	    int result = recurse ();
+	    result = recurse ();
 	    if (result != DWARF_CB_OK)
 	      return result;
 	  }
 
 	if (postvisit != NULL)
 	  {
-	    int result = (*postvisit) (depth + 1, &child, arg);
+	    result = (*postvisit) (depth + 1, &child, arg);
 	    if (result != DWARF_CB_OK)
 	      return result;
 	  }

libdwfl/ChangeLog

@@ -1,3 +1,11 @@
+2015-09-09  Chih-Hung Hsieh  <chh@google.com>
+	    Mark Wielaard  <mjw@redhat.com>
+
+	* dwfl_frame.c (dwfl_attach_state): Remove redundant NULL tests
+	on parameters declared with __nonnull_attribute__.
+	* libdwfl.h (dwfl_module_getelf): Don't mark first argument as
+	nonnull.
+
 2015-09-08  Mark Wielaard  <mjw@redhat.com>
 
 	* libdwflP.h (struct __libdwfl_pid_arg): Add elf and elf_fd.

libdwfl/dwfl_frame.c

@@ -143,7 +143,8 @@ dwfl_attach_state (Dwfl *dwfl, Elf *elf, pid_t pid,
 
   /* Reset any previous error, we are just going to try again.  */
   dwfl->attacherr = DWFL_E_NOERROR;
-  if (thread_callbacks == NULL || thread_callbacks->next_thread == NULL
+  /* thread_callbacks is declared NN */
+  if (thread_callbacks->next_thread == NULL
       || thread_callbacks->set_initial_registers == NULL)
     {
       dwfl->attacherr = DWFL_E_INVALID_ARGUMENT;

libdwfl/libdwfl.h

@@ -423,7 +423,7 @@ extern int dwfl_validate_address (Dwfl *dwfl,
    with the difference between addresses within the loaded module
    and those in symbol tables or Dwarf information referring to it.  */
 extern Elf *dwfl_module_getelf (Dwfl_Module *, GElf_Addr *bias)
-  __nonnull_attribute__ (1, 2);
+  __nonnull_attribute__ (2);
 
 /* Return the number of symbols in the module's symbol table,
    or -1 for errors.  */

libebl/ChangeLog

@@ -1,3 +1,11 @@
+2015-09-09  Chih-Hung Hsieh  <chh@google.com>
+
+	* ebldwarftoregno.c (ebl_dwarf_to_regno): Remove redundant NULL tests
+	on parameters declared with __nonnull_attribute__.
+	* eblinitreg.c (ebl_frame_nregs): Likewise.
+	* eblnormalizepc.c (ebl_normalize_pc): Likewise.
+	* eblunwind.c (ebl_unwind): Likewise.
+
 2015-09-04  Chih-Hung Hsieh  <chh@google.com>
 
 	* eblopenbackend.c (ebl_openbackend_machine): Replace K&R function

libebl/ebldwarftoregno.c

@@ -35,7 +35,6 @@
 bool
 ebl_dwarf_to_regno (Ebl *ebl, unsigned *regno)
 {
-  if (ebl == NULL)
-    return false;
+  /* ebl is declared NN */
   return ebl->dwarf_to_regno == NULL ? true : ebl->dwarf_to_regno (ebl, regno);
 }

libebl/eblinitreg.c

@@ -47,7 +47,8 @@ ebl_set_initial_registers_tid (Ebl *ebl, pid_t tid,
 size_t
 ebl_frame_nregs (Ebl *ebl)
 {
-  return ebl == NULL ? 0 : ebl->frame_nregs;
+  /* ebl is declared NN */
+  return ebl->frame_nregs;
 }
 
 GElf_Addr

libebl/eblnormalizepc.c

@@ -35,6 +35,7 @@
 void
 ebl_normalize_pc (Ebl *ebl, Dwarf_Addr *pc)
 {
-  if (ebl != NULL && ebl->normalize_pc != NULL)
+  /* ebl is declared NN */
+  if (ebl->normalize_pc != NULL)
     ebl->normalize_pc (ebl, pc);
 }

libebl/eblunwind.c

@@ -37,7 +37,8 @@ ebl_unwind (Ebl *ebl, Dwarf_Addr pc, ebl_tid_registers_t *setfunc,
 	    ebl_tid_registers_get_t *getfunc, ebl_pid_memory_read_t *readfunc,
 	    void *arg, bool *signal_framep)
 {
-  if (ebl == NULL || ebl->unwind == NULL)
+  /* ebl is declared NN */
+  if (ebl->unwind == NULL)
     return false;
   return ebl->unwind (ebl, pc, setfunc, getfunc, readfunc, arg, signal_framep);
 }