From 8cf30aa2be256eba07bb1cefb998c52326e846e7 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <victor.zverovich@gmail.com>
Date: Thu, 1 Feb 2018 21:28:20 -0800
Subject: [PATCH] Fix segfault on complex pointer formatting (#642)

---
 fmt/format.h        | 6 +++---
 test/format-test.cc | 4 ++++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/fmt/format.h b/fmt/format.h
index 23276591..6a8fa66b 100644
--- a/fmt/format.h
+++ b/fmt/format.h
@@ -3000,13 +3000,13 @@ typename BasicWriter<Char>::CharPtr
       CharPtr p = grow_buffer(fill_size);
       std::uninitialized_fill(p, p + fill_size, fill);
     }
-    CharPtr result = prepare_int_buffer(
-        num_digits, subspec, prefix, prefix_size);
+    std::ptrdiff_t offset = get(prepare_int_buffer(
+        num_digits, subspec, prefix, prefix_size)) - &buffer_[0];
     if (align == ALIGN_LEFT) {
       CharPtr p = grow_buffer(fill_size);
       std::uninitialized_fill(p, p + fill_size, fill);
     }
-    return result;
+    return internal::make_ptr(&buffer_[0], buffer_.size()) + offset;
   }
   unsigned size = prefix_size + num_digits;
   if (width <= size) {
diff --git a/test/format-test.cc b/test/format-test.cc
index c836541e..ec232e82 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1761,3 +1761,7 @@ void convert(int);
 TEST(FormatTest, ConvertCollision) {
   fmt::format("{}", 42);
 }
+
+TEST(FormatTest, Regression) {
+  fmt::format("...........{:<77777.7p}", "foo");
+}