diff --git a/NEWS b/NEWS
index 569c4ef..2d20b40 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,13 @@ GNU diffutils NEWS                                    -*- outline -*-
 
 ** Changes in behavior
 
+  In context-style diffs, diff prints a portion of a preceding "function"
+  line for each hunk, with --show-function-line=RE (-F) or
+  --show-c-function (-p).  Now, it trims leading blanks from such lines
+  before extracting a prefix.  This is useful especially when a function
+  line is so far indented that the name itself would be truncated or not
+  included in the limited-width substring that diff appends.
+
   diff once again reports a difference with the diagnostic
   "Binary files A and B differ" when at least one of the files
   appears to be binary.  From 2.8.4 through diffutils-2.9, it printed
diff --git a/src/context.c b/src/context.c
index e918134..84120f0 100644
--- a/src/context.c
+++ b/src/context.c
@@ -145,13 +145,15 @@ print_context_number_range (struct file_data const *file, lin a, lin b)
 static void
 print_context_function (FILE *out, char const *function)
 {
-  int i;
+  int i, j;
   putc (' ', out);
-  for (i = 0; i < 40 && function[i] != '\n'; i++)
+  for (i = 0; isspace ((unsigned char)function[i]) && function[i] != '\n'; i++)
     continue;
-  while (0 < i && isspace ((unsigned char) function[i - 1]))
-    i--;
-  fwrite (function, sizeof (char), i, out);
+  for (j = i; j < i + 40 && function[j] != '\n'; j++)
+    continue;
+  while (i < j && isspace ((unsigned char) function[j - 1]))
+    j--;
+  fwrite (function + i, sizeof (char), j - i, out);
 }
 
 /* Print a portion of an edit script in context format.