Index: llvm/test/tools/llvm-readobj/XCOFF/file-header.test
===================================================================
--- llvm/test/tools/llvm-readobj/XCOFF/file-header.test
+++ llvm/test/tools/llvm-readobj/XCOFF/file-header.test
@@ -1,7 +1,7 @@
 ## This is a general test for the --file-header option.
 
 # RUN: yaml2obj %s -o %t1
-# RUN: llvm-readobj %t1 --file-header | \
+# RUN: TZ=GMT llvm-readobj %t1 --file-header | \
 # RUN:   FileCheck %s --strict-whitespace --match-full-lines --check-prefix=FILEHEADER32
 
 #      FILEHEADER32:Format: aixcoff-rs6000
@@ -10,7 +10,7 @@
 # FILEHEADER32-NEXT:FileHeader {
 # FILEHEADER32-NEXT:  Magic: 0x1DF
 # FILEHEADER32-NEXT:  NumberOfSections: 1
-# FILEHEADER32-NEXT:  TimeStamp: 1970-01-01T00:00:01Z (0x1)
+# FILEHEADER32-NEXT:  TimeStamp: 1970-01-01 00:00:01 GMT (0x1)
 # FILEHEADER32-NEXT:  SymbolTableOffset: 0x3C
 # FILEHEADER32-NEXT:  SymbolTableEntries: 1
 # FILEHEADER32-NEXT:  OptionalHeaderSize: 0x0
Index: llvm/tools/llvm-readobj/XCOFFDumper.cpp
===================================================================
--- llvm/tools/llvm-readobj/XCOFFDumper.cpp
+++ llvm/tools/llvm-readobj/XCOFFDumper.cpp
@@ -98,10 +98,12 @@
     // tests will let us know.
     time_t TimeDate = TimeStamp;
 
-    char FormattedTime[21] = {};
-    size_t BytesWritten =
-        strftime(FormattedTime, 21, "%Y-%m-%dT%H:%M:%SZ", gmtime(&TimeDate));
-    if (BytesWritten)
+    char FormattedTime[80] = {};
+    struct tm local_tm;
+    size_t BytesFormatted =
+        strftime(FormattedTime, sizeof(FormattedTime), "%F %T %Z",
+                 localtime_r(&TimeDate, &local_tm));
+    if (BytesFormatted)
       W.printHex("TimeStamp", FormattedTime, TimeStamp);
     else
       W.printHex("Timestamp", TimeStamp);