diff --git a/flang/lib/Parser/prescan.cpp b/flang/lib/Parser/prescan.cpp
index 79cdaccf1fbfe..68d7d9f0c53c4 100644
--- a/flang/lib/Parser/prescan.cpp
+++ b/flang/lib/Parser/prescan.cpp
@@ -139,16 +139,18 @@ void Prescanner::Statement() {
         SkipSpaces();
       }
     } else {
-      // Compiler directive.  Emit normalized sentinel.
+      // Compiler directive.  Emit normalized sentinel, squash following spaces.
       EmitChar(tokens, '!');
       ++at_, ++column_;
       for (const char *sp{directiveSentinel_}; *sp != '\0';
            ++sp, ++at_, ++column_) {
         EmitChar(tokens, *sp);
       }
-      if (*at_ == ' ') {
+      if (*at_ == ' ' || *at_ == '\t') {
         EmitChar(tokens, ' ');
-        ++at_, ++column_;
+        while (*at_ == ' ' || *at_ == '\t') {
+          ++at_, ++column_;
+        }
       }
       tokens.CloseToken();
     }
diff --git a/flang/test/Parser/compiler-directives.f90 b/flang/test/Parser/compiler-directives.f90
index 88cfd0944faf0..67e8d5b292aa0 100644
--- a/flang/test/Parser/compiler-directives.f90
+++ b/flang/test/Parser/compiler-directives.f90
@@ -17,6 +17,7 @@ module m
   !dir$ integer
   !dir$ integer=64
   !dir$ integer = 64
+  !dir$  integer = 64
   PROC(4)
   !dir$ optimize:1
   !dir$ optimize : 1