Index: clang/lib/Format/ContinuationIndenter.cpp
===================================================================
--- clang/lib/Format/ContinuationIndenter.cpp
+++ clang/lib/Format/ContinuationIndenter.cpp
@@ -656,6 +656,7 @@
   int PPColumnCorrection = 0;
   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
       Previous.is(tok::hash) && State.FirstIndent > 0 &&
+      &Previous == State.Line->First &&
       (State.Line->Type == LT_PreprocessorDirective ||
        State.Line->Type == LT_ImportStatement)) {
     Spaces += State.FirstIndent;
Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -5385,6 +5385,10 @@
                "#endif",
                Style);
   Style.IndentPPDirectives = FormatStyle::PPDIS_AfterHash;
+  verifyFormat("#if 1\n"
+               "#  define __STR(x) #x\n"
+               "#endif",
+               Style);
   verifyFormat("#ifdef _WIN32\n"
                "#  define A 0\n"
                "#  ifdef VAR2\n"