Zebediah Figura : ntdll: Avoid comparing the result of pointer arithmetic to zero.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 539ef7c462852cf9b528e9d7b8fc6999ed8d5f2d
URL:    https://gitlab.winehq.org/wine/wine/-/commit/539ef7c462852cf9b528e9d7b8fc699...

Author: Zebediah Figura <zfigura(a)codeweavers.com>
Date:   Sun Sep 11 17:58:45 2022 -0500

ntdll: Avoid comparing the result of pointer arithmetic to zero.

gcc warns about this:

../wine/dlls/ntdll/unix/virtual.c: In function ‘mmap_add_reserved_area’:
../wine/dlls/ntdll/unix/virtual.c:241:9: error: the comparison will always evaluate as ‘true’ for the pointer operand in ‘(char *)addr + (sizetype)size’ must not be NULL [-Werror=address]
  241 |     if (!((char *)addr + size)) size--;  /* avoid wrap-around */
      |         ^

---

 dlls/ntdll/unix/virtual.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/unix/virtual.c b/dlls/ntdll/unix/virtual.c
index 96a5e095d16..e0aa410373e 100644
--- a/dlls/ntdll/unix/virtual.c
+++ b/dlls/ntdll/unix/virtual.c
@@ -238,7 +238,7 @@ static void mmap_add_reserved_area( void *addr, SIZE_T size )
     struct reserved_area *area;
     struct list *ptr;
 
-    if (!((char *)addr + size)) size--;  /* avoid wrap-around */
+    if (!((intptr_t)addr + size)) size--;  /* avoid wrap-around */
 
     LIST_FOR_EACH( ptr, &reserved_areas )
     {
@@ -287,7 +287,7 @@ static void mmap_remove_reserved_area( void *addr, SIZE_T size )
     struct reserved_area *area;
     struct list *ptr;
 
-    if (!((char *)addr + size)) size--;  /* avoid wrap-around */
+    if (!((intptr_t)addr + size)) size--;  /* avoid wrap-around */
 
     ptr = list_head( &reserved_areas );
     /* find the first area covering address */