[gcc(refs/users/marxin/heads/marxin-gcc-benchmark-branch)] Document ASLR for Precompiled Headers.

[Martin Liska]

https://gcc.gnu.org/g:f4239581925d6a9fba049f8f771e909a7a5e5ce7

commit f4239581925d6a9fba049f8f771e909a7a5e5ce7
Author: Martin Liska <mliska@suse.cz>
Date:   Wed Feb 5 09:55:09 2020 +0100

    Document ASLR for Precompiled Headers.
    
            PR c++/92717
            * doc/invoke.texi: Document that one should
            not combine ASLR and -fpch.

Diff:
---
 gcc/ChangeLog       | 6 ++++++
 gcc/doc/invoke.texi | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d6b5ded32a4..85083e8bc34 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2020-02-05  Martin Liska  <mliska@suse.cz>
+
+	PR c++/92717
+	* doc/invoke.texi: Document that one should
+	not combine ASLR and -fpch.
+
 2020-02-04  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/93538
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 4dec0c8326b..35b341e759f 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -31106,6 +31106,10 @@ precompiled header.  The following are known to be safe:
 -fsched-verbose=@var{number}  -fschedule-insns  -fvisibility= @gol
 -pedantic-errors}
 
+@item Address space layout randomization (ASLR) can lead to not binary identical
+PCH files.  If you rely on stable PCH file contents disable ASLR when generating
+PCH files.
+
 @end itemize
 
 For all of these except the last, the compiler automatically