dso, execve{,at}, posix_spawn: do not run OpenBSD dynamic loader

The ELF dynamic loader in OpenBSD is not executable.

	-bash-5.2$ ls -l /usr/libexec/ld.so
	-r--r--r--  1 root  bin  359016 Oct  8 19:57 /usr/libexec/ld.so

This conditionizes the code to run the dynamic loader if not OpenBSD.

dso.c

@@ -696,6 +696,7 @@ static int __fld_needed(int fd,
 	return __path_iterate(needed, __ld_needed_callback, &ctx);
 }
 
+#ifndef __OpenBSD__
 static int __ld_needed(const char *path,
 		       const char *rpath,
 		       const char *ld_library_path,
@@ -721,6 +722,7 @@ static int __ld_needed(const char *path,
 
 	return ret;
 }
+#endif
 
 struct __ld_open_needed_context {
 	int flags;
@@ -3538,7 +3540,7 @@ hidden ssize_t __dl_access(const char *path, int mode, char *buf,
 			     bufsiz);
 }
 
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 static const char *__root_basepath(const char *path)
 {
 	const char *root;

execve.c

@@ -19,7 +19,7 @@
 
 extern int next_faccessat(int, const char *, int, int);
 
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 extern int __ldso_execve(const char *, char * const[], char * const[]);
 #endif
 
@@ -207,7 +207,7 @@ int execve(const char *path, char * const argv[], char * const envp[])
 	off += siz+1; /* NULL-terminated */
 
 loader:
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 	/* It is the dynamic loader */
 	ret = __is_ldso(__basename(path));
 	/* Try to run the dynamic loader internaly... */

execveat.c

@@ -16,7 +16,7 @@
 
 #include "iamroot.h"
 
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 extern int __ldso_execveat(int, const char *, char * const[], char * const[]);
 #endif
 
@@ -146,7 +146,7 @@ int execveat(int dfd, const char *path, char * const argv[],
 	off += siz+1; /* NULL-terminated */
 
 loader:
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 	/* It is the dynamic loader */
 	ret = __is_ldso(__basename(path));
 	/* Try to run the dynamic loader internaly... */

posix_spawn.c

@@ -17,7 +17,7 @@
 
 #include "iamroot.h"
 
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 extern int __ldso_posix_spawn(pid_t *,
 			      const char *,
 			      const posix_spawn_file_actions_t *,
@@ -159,7 +159,7 @@ int posix_spawn(pid_t *pid, const char *path,
 	off += siz+1; /* NULL-terminated */
 
 loader:
-#ifndef __NetBSD__
+#if !defined __NetBSD__ && !defined __OpenBSD__
 	/* It is the dynamic loader */
 	ret = __is_ldso(__basename(path));
 	/* Try to run the dynamic loader internaly... */