[Valgrind-developers] [valgrind] Change behaviour of posix_memalign for Solaris

[Paul F. <pa...@so...>]

https://sourceware.org/git/gitweb.cgi?p=valgrind.git;h=33ce1bf1cb01b49a441e43a11f5c2de21712e60b

commit 33ce1bf1cb01b49a441e43a11f5c2de21712e60b
Author: Paul Floyd <pj...@wa...>
Date:   Tue Feb 28 21:21:05 2023 +0100

    Change behaviour of posix_memalign for Solaris
    
    It returns NULL and 0 status whilst most other platforms
    allocatae some undefined amount of memory (which is allowed
    by posix).
    
    Update the posix_memalign test as well.
    
    Finally remove some clang warnings about alignment.

Diff:
---
 coregrind/m_replacemalloc/vg_replace_malloc.c | 16 +++++++++++++++-
 memcheck/tests/freebsd/Makefile.am            |  2 ++
 memcheck/tests/posix_memalign.c               | 18 +++++++++++++-----
 3 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/coregrind/m_replacemalloc/vg_replace_malloc.c b/coregrind/m_replacemalloc/vg_replace_malloc.c
index 5ded69e969..cc38d665bf 100644
--- a/coregrind/m_replacemalloc/vg_replace_malloc.c
+++ b/coregrind/m_replacemalloc/vg_replace_malloc.c
@@ -1817,6 +1817,12 @@ extern int *___errno (void) __attribute__((weak));
 
 /*---------------------- posix_memalign ----------------------*/
 
+#if defined(VGO_solaris)
+#define VG_POSIX_MEMALIGN_SIZE_0_RETURN_NULL 1
+#else
+#define VG_POSIX_MEMALIGN_SIZE_0_RETURN_NULL 0
+#endif
+
 #define POSIX_MEMALIGN(soname, fnname) \
    \
    int VG_REPLACE_FUNCTION_EZU(10160,soname,fnname) \
@@ -1837,6 +1843,12 @@ extern int *___errno (void) __attribute__((weak));
           || (alignment & (alignment - 1)) != 0) { \
          return VKI_EINVAL; \
       } \
+      if (VG_POSIX_MEMALIGN_SIZE_0_RETURN_NULL && \
+          size == 0U) { \
+         /* no allocation for zro size on Solaris/Illumos */ \
+         *memptr = NULL; \
+         return 0; \
+      } \
       /* Round up to minimum alignment if necessary. */ \
       if (alignment < VG_MIN_MALLOC_SZB) \
           alignment = VG_MIN_MALLOC_SZB; \
@@ -1861,7 +1873,9 @@ extern int *___errno (void) __attribute__((weak));
  POSIX_MEMALIGN(SO_SYN_MALLOC,    posix_memalign);
 
 #elif defined(VGO_darwin)
- //POSIX_MEMALIGN(VG_Z_LIBC_SONAME, posix_memalign);
+#if (DARWIN_VERSIO >= DARWIN_10_6)
+ POSIX_MEMALIGN(VG_Z_LIBC_SONAME, posix_memalign);
+#endif
 
 #elif defined(VGO_solaris)
  POSIX_MEMALIGN(VG_Z_LIBC_SONAME, posix_memalign);
diff --git a/memcheck/tests/freebsd/Makefile.am b/memcheck/tests/freebsd/Makefile.am
index 631d0efe9e..2259e1efb8 100644
--- a/memcheck/tests/freebsd/Makefile.am
+++ b/memcheck/tests/freebsd/Makefile.am
@@ -134,3 +134,5 @@ scalar_CFLAGS = ${AM_CFLAGS} -g
 errno_aligned_allocs_CFLAGS = ${AM_CFLAGS} @FLAG_W_NO_NON_POWER_OF_TWO_ALIGNMENT@
 
 extattr_CFLAGS = ${AM_CFLAGS} @FLAG_W_NO_UNUSED_BUT_SET_VARIABLE@
+
+memalign_CFLAGS = ${AM_CFLAGS} @FLAG_W_NO_NON_POWER_OF_TWO_ALIGNMENT@
diff --git a/memcheck/tests/posix_memalign.c b/memcheck/tests/posix_memalign.c
index 415c6c025b..219df2ffd8 100644
--- a/memcheck/tests/posix_memalign.c
+++ b/memcheck/tests/posix_memalign.c
@@ -28,25 +28,33 @@ int main ( void )
 
 #  define PM(a,b,c) posix_memalign((void**)a, b, c)
 
+   // test for size 0
+   res = PM(&p, 64, 0);
+#if defined(VGO_solaris)
+   assert(NULL == p);
+#else
+   assert(0 == res && p && 0 == (long)p % 64);
+#endif
+
    res = PM(&p, -1,100);      assert(EINVAL == res);
    res = PM(&p, 0, 100);      assert(EINVAL == res);
    res = PM(&p, 1, 100);      assert(EINVAL == res);
    res = PM(&p, 2, 100);      assert(EINVAL == res);
    res = PM(&p, 3, 100);      assert(EINVAL == res);
    res = PM(&p, sizeof(void*), 100);
-                              assert(0 == res && 0 == (long)p % sizeof(void*));
+                              assert(0 == res && p && 0 == (long)p % sizeof(void*));
 
    res = PM(&p, 31, 100);     assert(EINVAL == res);
-   res = PM(&p, 32, 100);     assert(0 == res && 0 == (long)p % 32);
+   res = PM(&p, 32, 100);     assert(0 == res && p && 0 == (long)p % 32);
    res = PM(&p, 33, 100);     assert(EINVAL == res);
 
    res = PM(&p, 4095, 100);   assert(EINVAL == res);
-   res = PM(&p, 4096, 100);   assert(0 == res && 0 == (long)p % 4096); 
+   res = PM(&p, 4096, 100);   assert(0 == res && p && 0 == (long)p % 4096);
    res = PM(&p, 4097, 100);   assert(EINVAL == res);
 
-   res = PM(&p, 4 * 1024 * 1024, 100);   assert(0 == res 
+   res = PM(&p, 4 * 1024 * 1024, 100);   assert(0 == res && p
                                                 && 0 == (long)p % (4 * 1024 * 1024));
-   res = PM(&p, 16 * 1024 * 1024, 100);   assert(0 == res 
+   res = PM(&p, 16 * 1024 * 1024, 100);   assert(0 == res &&p
                                                 && 0 == (long)p % (16 * 1024 * 1024));
 #endif
 }