diff --git a/libc/bionic/libc_logging.cpp b/libc/bionic/libc_logging.cpp
index 88d9790..cdbf723 100644
--- a/libc/bionic/libc_logging.cpp
+++ b/libc/bionic/libc_logging.cpp
@@ -230,6 +230,7 @@
 /* Perform formatted output to an output target 'o' */
 template <typename Out>
 static void out_vformat(Out& o, const char* format, va_list args) {
+    int caller_errno = errno;
     int nn = 0;
 
     for (;;) {
@@ -380,7 +381,7 @@
             buffer[1] = '\0';
         } else if (c == 'm') {
             // syslog-like %m for strerror(errno).
-            str = strerror(errno);
+            str = strerror(caller_errno);
         } else {
             __assert(__FILE__, __LINE__, "conversion specifier unsupported");
         }