Document ld -t behaviour

[external/binutils.git] / ld / ld.texi

diff --git a/ld/ld.texi b/ld/ld.texi
index cc0d220..9bede66 100644 (file)
--- a/ld/ld.texi
+++ b/ld/ld.texi
@@ -961,7 +961,11 @@ Enabled by default.
 @cindex input files, displaying
 @item -t
 @itemx --trace
-Print the names of the input files as @command{ld} processes them.
+Print the names of the input files as @command{ld} processes them.  If
+@samp{-t} is given twice then members within archives are also printed.
+@samp{-t} output is useful to generate a list of all the object files
+and scripts involved in linking, for example, when packaging files for
+a linker bug report.
 
 @kindex -T @var{script}
 @kindex --script=@var{script}
@@ -2392,6 +2396,28 @@ you should not put the definition of @code{__real_malloc} in the same
 file as @code{__wrap_malloc}; if you do, the assembler may resolve the
 call before the linker has a chance to wrap it to @code{malloc}.
 
+Only undefined references are replaced by the linker.  So, translation unit
+internal references to @var{symbol} are not resolved to
+@code{__wrap_@var{symbol}}.  In the next example, the call to @code{f} in
+@code{g} is not resolved to @code{__wrap_f}.
+
+@smallexample
+int
+f (void)
+@{
+  return 123;
+@}
+
+int
+g (void)
+@{
+  return f();
+@}
+@end smallexample
+
+Please keep in mind that with link-time optimization (LTO) enabled, your whole
+program may be a translation unit.
+
 @kindex --eh-frame-hdr
 @kindex --no-eh-frame-hdr
 @item --eh-frame-hdr