work around "signal loses thread pointer" issue with "approach 2"

[musl] / src / signal / sigaction.c

diff --git a/src/signal/sigaction.c b/src/signal/sigaction.c
index 18956c6..5bc9383 100644 (file)
--- a/src/signal/sigaction.c
+++ b/src/signal/sigaction.c
@@ -3,9 +3,13 @@
 #include <errno.h>
 #include "syscall.h"
 #include "pthread_impl.h"
+#include "libc.h"
 
 void __restore(), __restore_rt();
 
+static pthread_t dummy(void) { return 0; }
+weak_alias(dummy, __pthread_self_def);
+
 int __libc_sigaction(int sig, const struct sigaction *sa, struct sigaction *old)
 {
        struct {
@@ -23,6 +27,7 @@ int __libc_sigaction(int sig, const struct sigaction *sa, struct sigaction *old)
                pksa = (long)&ksa;
        }
        if (old) pkold = (long)&kold;
+       __pthread_self_def();
        if (syscall(SYS_rt_sigaction, sig, pksa, pkold, 8))
                return -1;
        if (old) {