From: Thomas Monjalon <thomas.monjalon@6wind.com>
Date: Fri, 12 Jul 2013 10:54:35 +0000 (+0200)
Subject: eal: fix type of pointer arithmetic result
X-Git-Tag: spdx-start~10974
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=894f5cc4411e1d853f80af4db6c74c1ec413f992;p=dpdk.git

eal: fix type of pointer arithmetic result

Adding or subtracting a value to a pointer makes a new pointer
of unknown type.
So typeof() is replaced by (void*) in RTE_PTR_ADD() and RTE_PTR_SUB().

But RTE_PTR_ALIGN_* macros have in their explicit API to return a pointer
of the same type. Since RTE_PTR_ALIGN_CEIL is based on RTE_PTR_ADD, a
typeof() is added to keep the original behaviour.

Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
---

diff --git a/app/test/test_common.c b/app/test/test_common.c
index 36feedcc55..12be1f4732 100644
--- a/app/test/test_common.c
+++ b/app/test/test_common.c
@@ -61,9 +61,9 @@ test_macros(int __rte_unused unused_parm)
 
 	RTE_SET_USED(unused);
 
-	if (RTE_PTR_ADD(SMALLER, PTR_DIFF) != BIGGER)
+	if ((uintptr_t)RTE_PTR_ADD(SMALLER, PTR_DIFF) != BIGGER)
 		FAIL_MACRO(RTE_PTR_ADD);
-	if (RTE_PTR_SUB(BIGGER, PTR_DIFF) != SMALLER)
+	if ((uintptr_t)RTE_PTR_SUB(BIGGER, PTR_DIFF) != SMALLER)
 		FAIL_MACRO(RTE_PTR_SUB);
 	if (RTE_PTR_DIFF(BIGGER, SMALLER) != PTR_DIFF)
 		FAIL_MACRO(RTE_PTR_DIFF);
diff --git a/lib/librte_eal/common/include/rte_common.h b/lib/librte_eal/common/include/rte_common.h
index 0cf328ecd8..b6ea7f0674 100644
--- a/lib/librte_eal/common/include/rte_common.h
+++ b/lib/librte_eal/common/include/rte_common.h
@@ -69,12 +69,12 @@ extern "C" {
 /**
  * add a byte-value offset from a pointer
  */
-#define RTE_PTR_ADD(ptr, x) ((typeof(ptr))((uintptr_t)(ptr) + (x)))
+#define RTE_PTR_ADD(ptr, x) ((void*)((uintptr_t)(ptr) + (x)))
 
 /**
  * subtract a byte-value offset from a pointer
  */
-#define RTE_PTR_SUB(ptr, x) ((typeof(ptr))((uintptr_t)ptr - (x)))
+#define RTE_PTR_SUB(ptr, x) ((void*)((uintptr_t)ptr - (x)))
 
 /**
  * get the difference between two pointer values, i.e. how far apart
@@ -130,7 +130,7 @@ rte_align_floor_int(uintptr_t ptr, uintptr_t align)
  * must be a power-of-two value.
  */
 #define RTE_PTR_ALIGN_CEIL(ptr, align) \
-	RTE_PTR_ALIGN_FLOOR(RTE_PTR_ADD(ptr, (align) - 1), align)
+	RTE_PTR_ALIGN_FLOOR((typeof(ptr))RTE_PTR_ADD(ptr, (align) - 1), align)
 
 /**
  * Macro to align a value to a given power-of-two. The resultant value