diff --git a/README.md b/README.md
index 29e6b7b4e8708451c22f8cc5ea590b65e15c8ab2..6b50981b3965262c1e3fe81eaec7266e925672d1 100644
--- a/README.md
+++ b/README.md
@@ -75,11 +75,18 @@ Wrapped headers and replaced functions are:
<td>OSX10.6, OSX10.12 (open_memstream)</td>
</tr>
<tr>
- <td rowspan="2"><code>stdlib.h</code></td>
- <td>Adds <code>posix_memalign</code> functional replacement, and wraps <code>realpath</code>
- to accept a <code>NULL</code> buffer argument</td>
+ <td rowspan="4"><code>stdlib.h</code></td>
+ <td>Adds <code>posix_memalign</code> functional replacement</td>
<td>OSX10.5</td>
</tr>
+ <tr>
+ <td>Wraps <code>realpath</code> to accept a <code>NULL</code> buffer argument</td>
+ <td>OSX10.5</td>
+ </tr>
+ <tr>
+ <td>Fixes non-POSIX <code>realpath</code> in 10.6</td>
+ <td>OSX10.6</td>
+ </tr>
<tr>
<td>Adds <code>arc4random_uniform</code> and <code>arc4random_buf</code> functions</td>
<td>OSX10.6</td>
diff --git a/include/MacportsLegacySupport.h b/include/MacportsLegacySupport.h
index 9ac8b2ef1fee9f7eaee21a027f3a93ed63b57140..cdb6c503761774aa39dd2545eb90643f9bca95b9 100644
--- a/include/MacportsLegacySupport.h
+++ b/include/MacportsLegacySupport.h
@@ -230,7 +230,13 @@
/* The addition uses an #ifndef, so no feature flag is necessary */
/* realpath() on < 10.6 does not support modern NULL buffer usage */
-#define __MPLS_LIB_SUPPORT_REALPATH_WRAP__ (__MPLS_TARGET_OSVER < 1060)
+#define __MPLS_LIB_SUPPORT_REALPATH_ALLOC__ (__MPLS_TARGET_OSVER < 1060)
+
+/* Also, 10.6 non-POSIX realpath() (32-bit only) with a nonexistent path and
+ * a NULL buffer returns an unsafe pointer to an internal buffer. */
+#define __MPLS_LIB_SUPPORT_REALPATH_NONEX_FIX__ (__MPLS_TARGET_OSVER >= 1060 \
+ && __MPLS_TARGET_OSVER < 1070 \
+ && !__MPLS_64BIT)
/* fsetattrlistat, fgetattrlistat */
#define __MPLS_SDK_SUPPORT_FSETATTRLIST__ (__MPLS_SDK_MAJOR < 1060)
@@ -316,10 +322,18 @@
#define __MPLS_LIB_SUPPORT_PTHREAD_SETNAME_NP__ (__MPLS_TARGET_OSVER < 1060)
/* Compound macros, bundling functionality needed by multiple single features. */
-#define __MPLS_SDK_NEED_ATCALL_MACROS__ (__MPLS_SDK_SUPPORT_ATCALLS__ || __MPLS_SDK_SUPPORT_SETATTRLISTAT__)
-
-#define __MPLS_SDK_NEED_BEST_FCHDIR__ (__MPLS_SDK_SUPPORT_FDOPENDIR__ || __MPLS_SDK_SUPPORT_ATCALLS__ || __MPLS_SDK_SUPPORT_SETATTRLISTAT__)
-#define __MPLS_LIB_NEED_BEST_FCHDIR__ (__MPLS_LIB_SUPPORT_FDOPENDIR__ || __MPLS_LIB_SUPPORT_ATCALLS__ || __MPLS_LIB_SUPPORT_SETATTRLISTAT__)
+#define __MPLS_SDK_NEED_ATCALL_MACROS__ (__MPLS_SDK_SUPPORT_ATCALLS__ \
+ || __MPLS_SDK_SUPPORT_SETATTRLISTAT__)
+
+#define __MPLS_SDK_NEED_BEST_FCHDIR__ (__MPLS_SDK_SUPPORT_FDOPENDIR__ \
+ || __MPLS_SDK_SUPPORT_ATCALLS__ \
+ || __MPLS_SDK_SUPPORT_SETATTRLISTAT__)
+#define __MPLS_LIB_NEED_BEST_FCHDIR__ (__MPLS_LIB_SUPPORT_FDOPENDIR__ \
+ || __MPLS_LIB_SUPPORT_ATCALLS__ \
+ || __MPLS_LIB_SUPPORT_SETATTRLISTAT__)
+
+#define __MPLS_LIB_SUPPORT_REALPATH_WRAP__ (__MPLS_LIB_SUPPORT_REALPATH_ALLOC__ \
+ || __MPLS_LIB_SUPPORT_REALPATH_NONEX_FIX__)
/* UUIDs - for now, just add missing typedef statements */
#define __MPLS_SDK_SUPPORT_UUID__ (__MPLS_SDK_MAJOR < 1060)
diff --git a/src/add_symbols.c b/src/add_symbols.c
index 224372811d4a7560a5ee4063a02e76ed48c7da47..7f132fec31d7724da44d115e4bfd25d6f87cc1ee 100644
--- a/src/add_symbols.c
+++ b/src/add_symbols.c
@@ -5,7 +5,7 @@ extern const char posix_memalign_tmp4 __asm("$ld$add$os10.4$_posix_memalign"); _
extern const char posix_memalign_tmp5 __asm("$ld$add$os10.5$_posix_memalign"); __attribute__((visibility("default"))) const char posix_memalign_tmp5 = 0;
#endif
-#if !(__MPLS_LIB_SUPPORT_REALPATH_WRAP__)
+#if !(__MPLS_LIB_SUPPORT_REALPATH_ALLOC__)
extern const char realpath_tmp4 __asm("$ld$add$os10.4$_realpath"); __attribute__((visibility("default"))) const char realpath_tmp4 = 0;
extern const char realpath_tmp5 __asm("$ld$add$os10.5$_realpath$DARWIN_EXTSN"); __attribute__((visibility("default"))) const char realpath_tmp5 = 0;
#endif
diff --git a/src/realpath.c b/src/realpath.c
index dc48fa0b365bfeefcb4e0c4d0365006b67177e8f..3e790051b94e698c337b740231e2c6613023b02c 100644
--- a/src/realpath.c
+++ b/src/realpath.c
@@ -54,8 +54,13 @@
/* Function type for realpath() */
typedef char *rp_func_t(const char * __restrict, char * __restrict);
-/* Macro defining all versions */
-/* Note that the UNIX2003 version never exists in 64-bit builds. */
+/*
+ * Macro defining all versions
+ * Note that the UNIX2003 version never exists in 64-bit builds.
+ * Also note that the 10.6 "nonext" fix only needs the basic version.
+ */
+
+# if __MPLS_LIB_SUPPORT_REALPATH_ALLOC__
#if !__MPLS_64BIT
@@ -72,6 +77,14 @@ typedef char *rp_func_t(const char * __restrict, char * __restrict);
#endif /* 64-bit */
+#endif /* __MPLS_LIB_SUPPORT_REALPATH_ALLOC__ */
+
+#if __MPLS_LIB_SUPPORT_REALPATH_NONEX_FIX__
+
+#define RP_ALL RP_ENT(,,basic)
+
+#endif /* __MPLS_LIB_SUPPORT_REALPATH_NONEX_FIX__ */
+
/* Table of indices of versions */
#define RP_ENT(d,x,t) rp_##t,
typedef enum {
@@ -140,6 +153,8 @@ realpath##d##x(const char * __restrict file_name, \
RP_ALL
#undef RP_ENT
+# if __MPLS_LIB_SUPPORT_REALPATH_ALLOC__
+
/*
* Compatibility function to avoid the need to rebuild existing binaries
* built with the old wrapper-macro implementation (between Jan-2019 and
@@ -162,4 +177,6 @@ macports_legacy_realpath(const char * __restrict file_name,
return realpath_internal(file_name, resolved_name, RP_DEFAULT);
}
+#endif /* __MPLS_LIB_SUPPORT_REALPATH_ALLOC__ */
+
#endif /*__MPLS_LIB_SUPPORT_REALPATH_WRAP__*/
diff --git a/test/test_realpath_compat.c b/test/test_realpath_compat.c
index 815875899fd3c928c329681e2086d349f5d11239..d9a890f1c200c8d69fae2ee765542d0f48413dd7 100644
--- a/test/test_realpath_compat.c
+++ b/test/test_realpath_compat.c
@@ -12,14 +12,14 @@
/* MP support header */
#include "MacportsLegacySupport.h"
-#if __MPLS_LIB_SUPPORT_REALPATH_WRAP__
+#if __MPLS_LIB_SUPPORT_REALPATH_ALLOC__
#define TEST_MACPORTS_LEGACY_REALPATH
#include "test_realpath.c"
-#else /* !__MPLS_LIB_SUPPORT_REALPATH_WRAP__ */
+#else /* !__MPLS_LIB_SUPPORT_REALPATH_ALLOC__ */
int main(){ return 0; }
-#endif /* !__MPLS_LIB_SUPPORT_REALPATH_WRAP__ */
+#endif /* !__MPLS_LIB_SUPPORT_REALPATH_ALLOC__ */