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diff --git a/ld/ld.texinfo b/ld/ld.texinfo
index 6c74ff5..1830306 100644
--- a/ld/ld.texinfo
+++ b/ld/ld.texinfo
@@ -2718,7 +2718,10 @@ You can change the behaviour of @command{ld} with the environment variables
@ifclear SingleFormat
@code{GNUTARGET},
@end ifclear
-@code{LDEMULATION} and @code{COLLECT_NO_DEMANGLE}.
+@code{LDEMULATION},
+@code{COLLECT_NO_DEMANGLE}
+and
+@code{LD_ALTEXEC}.
@ifclear SingleFormat
@kindex GNUTARGET
@@ -2756,6 +2759,12 @@ a similar fashion by the @code{gcc} linker wrapper program. The default
may be overridden by the @samp{--demangle} and @samp{--no-demangle}
options.
+@kindex LD_ALTEXEC
+@cindex alternative linker
+@code{LD_ALTEXEC} sets alternative linker. @command{ld} executes,
+and passes control to this alternative linker. For instance one
+can set @code{LD_ALTEXEC=echo} to debug linker command line.
+
@c man end
@end ifset
diff --git a/ld/ldmain.c b/ld/ldmain.c
index b2810a7..8b5612f 100644
--- a/ld/ldmain.c
+++ b/ld/ldmain.c
@@ -52,6 +52,7 @@
#endif
#include <string.h>
+#include <errno.h>
#ifdef HAVE_SBRK
#if !HAVE_DECL_SBRK
@@ -173,12 +174,38 @@ ld_cleanup (void)
unlink_if_ordinary (output_filename);
}
+static void
+maybe_altexec(char **argv)
+{
+ char *LD_ALTEXEC;
+
+ /* If LD_ALTEXEC is not set or is empty, just return */
+ LD_ALTEXEC = getenv("LD_ALTEXEC");
+ if (LD_ALTEXEC == NULL)
+ return;
+
+ if (*LD_ALTEXEC == '\0')
+ return;
+
+ /* Unset LD_ALTEXEC for case when it points to this program itself ;-) */
+ if (unsetenv("LD_ALTEXEC"))
+ exit(errno);
+
+ argv[0] = LD_ALTEXEC;
+ execvp(LD_ALTEXEC, argv);
+
+ /* We are here only if execvp() failed */
+ exit(errno);
+}
+
int
main (int argc, char **argv)
{
char *emulation;
long start_time = get_run_time ();
+ maybe_altexec(argv);
+
#if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES)
setlocale (LC_MESSAGES, "");
#endif
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