--- old/src/java.base/share/native/libjli/java.c	2020-03-26 14:02:35.011837437 +0800
+++ new/src/java.base/share/native/libjli/java.c	2020-03-26 14:02:34.835838060 +0800
@@ -241,7 +241,7 @@
     char *main_class = NULL;
     int ret;
     InvocationFunctions ifn;
-    jlong start, end;
+    jlong start = 0, end = 0;
     char jvmpath[MAXPATHLEN];
     char jrepath[MAXPATHLEN];
     char jvmcfg[MAXPATHLEN];
@@ -408,7 +408,7 @@
     jmethodID mainID;
     jobjectArray mainArgs;
     int ret = 0;
-    jlong start, end;
+    jlong start, end = 0;
 
     RegisterThread();
 
@@ -1618,7 +1618,7 @@
     jmethodID mid;
     jstring str;
     jobject result;
-    jlong start, end;
+    jlong start = 0, end = 0;
     jclass cls = GetLauncherHelperClass(env);
     NULL_CHECK0(cls);
     if (JLI_IsTraceLauncher()) {
@@ -1633,7 +1633,7 @@
                                                         USE_STDERR, mode, str));
 
     if (JLI_IsTraceLauncher()) {
-        end   = CounterGet();
+        end = CounterGet();
         printf("%ld micro seconds to load main class\n",
                (long)(jint)Counter2Micros(end-start));
         printf("----%s----\n", JLDEBUG_ENV_ENTRY);
@@ -2080,7 +2080,7 @@
     char line[MAXPATHLEN+20];
     int cnt = 0;
     int lineno = 0;
-    jlong start, end;
+    jlong start = 0, end = 0;
     int vmType;
     char *tmpPtr;
     char *altVMName = NULL;
@@ -2172,7 +2172,7 @@
     knownVMsCount = cnt;
 
     if (JLI_IsTraceLauncher()) {
-        end   = CounterGet();
+        end = CounterGet();
         printf("%ld micro seconds to parse jvm.cfg\n",
                (long)(jint)Counter2Micros(end-start));
     }
--- old/src/java.base/unix/native/libjli/java_md_solinux.h	2020-03-26 14:02:35.659835143 +0800
+++ new/src/java.base/unix/native/libjli/java_md_solinux.h	2020-03-26 14:02:35.471835809 +0800
@@ -34,8 +34,22 @@
 #define CounterGet()              (gethrtime()/1000)
 #define Counter2Micros(counts)    (counts)
 #else  /* ! HAVE_GETHRTIME */
-#define CounterGet()              (0)
-#define Counter2Micros(counts)    (1)
+/*
+ *  * Add gethrtime() implementation for launch time debug on Linux.
+ *   */
+#include <sys/time.h>
+inline uint64_t gethrtime() {
+  uint64_t result = 0;
+  struct timeval tv;
+  if (gettimeofday(&tv, NULL) != -1) {
+    result = 1000000LL * (uint64_t)tv.tv_sec;
+    result += (uint64_t)tv.tv_usec;
+  }
+  return result;
+}
+
+#define CounterGet()              (gethrtime())
+#define Counter2Micros(counts)    (counts)
 #endif /* HAVE_GETHRTIME */
 
 /* pointer to environment */