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This causes pahole to use '-j1' (single thread) when SOURCE_DATE_EPOCH
is set, to ensure it produces reproducible output.

diff --git a/pahole.c b/pahole.c
index 6fc4ed6..a4e306f 100644
--- a/pahole.c
+++ b/pahole.c
@@ -1687,8 +1687,11 @@ static error_t pahole__options_parser(int key, char *arg,
 		  class_name = arg;			break;
 	case 'j':
 #if _ELFUTILS_PREREQ(0, 178)
-		  conf_load.nr_jobs = arg ? atoi(arg) :
-					    sysconf(_SC_NPROCESSORS_ONLN) * 1.1;
+		  // Force single thread if reproducibility is desirable.
+		  if (!getenv("SOURCE_DATE_EPOCH")) {
+			  conf_load.nr_jobs = arg ? atoi(arg) :
+						    sysconf(_SC_NPROCESSORS_ONLN) * 1.1;
+		  }
 #else
 		  fputs("pahole: Multithreading requires elfutils >= 0.178. Continuing with a single thread...\n", stderr);
 #endif
