[commits] r5273 - in /fsf/trunk/libc: ChangeLog FAQ FAQ.in

[eglibc@xxxxxxxxxx]

Author: eglibc
Date: Sat Feb 23 00:08:59 2008
New Revision: 5273

Log:
Import glibc-mainline for 2008-02-23

Modified:
    fsf/trunk/libc/ChangeLog
    fsf/trunk/libc/FAQ
    fsf/trunk/libc/FAQ.in

Modified: fsf/trunk/libc/ChangeLog
==============================================================================
--- fsf/trunk/libc/ChangeLog (original)
+++ fsf/trunk/libc/ChangeLog Sat Feb 23 00:08:59 2008
@@ -1,3 +1,10 @@
+2008-02-22  Andreas Jaeger  <aj@xxxxxxx>,
+	    Carlos O'Donell <carlos@xxxxxxxxxxxxxxxx>
+
+	[BZ #5012]
+	* FAQ.in: Describe why glibc needs to be compiled with
+	optimization.
+
 2008-02-19  Roland McGrath  <roland@xxxxxxxxxx>
 
 	* elf/elf.h (SHT_GNU_ATTRIBUTES): New macro.

Modified: fsf/trunk/libc/FAQ
==============================================================================
--- fsf/trunk/libc/FAQ (original)
+++ fsf/trunk/libc/FAQ Sat Feb 23 00:08:59 2008
@@ -50,6 +50,9 @@
 1.21.	Which compiler should I use for powerpc64?
 1.22.	`make' fails when running rpcgen the first time,
 	what is going on? How do I fix this?
+1.23.	Why do I get:
+	`#error "glibc cannot be compiled without optimization"',
+	when trying to compile GNU libc with GNU CC?
 
 2. Installation and configuration issues
 
@@ -484,12 +487,12 @@
 failure should be looked into.  Depending on the failures, you probably
 should not install the library at all.
 
-You should consider using the `glibcbug' script to report the failure,
-providing as much detail as possible.  If you run a test directly, please
-remember to set up the environment correctly.  You want to test the compiled
-library - and not your installed one.  The best way is to copy the exact
-command line which failed and run the test from the subdirectory for this
-test in the sources.
+You should consider reporting it in bugzilla
+<http://sourceware.org/bugzilla/> providing as much detail as possible.
+If you run a test directly, please remember to set up the environment
+correctly. You want to test the compiled library - and not your installed
+one. The best way is to copy the exact command line which failed and run
+the test from the subdirectory for this test in the sources.
 
 There are some failures which are not directly related to the GNU libc:
 - Some compilers produce buggy code.  No compiler gets single precision
@@ -588,6 +591,32 @@
 yourself. Please remember that for each architecture there may be various
 patches required to get glibc HEAD into a runnable state. The best course
 of action is to determine if you have all the required patches.
+
+
+1.23.	Why do I get:
+	`#error "glibc cannot be compiled without optimization"',
+	when trying to compile GNU libc with GNU CC?
+
+{AJ,CO} There are a couple of reasons why the GNU C library will not work
+correctly if it is not complied with optimzation.
+
+In the early startup of the dynamic loader (_dl_start), before
+relocation of the PLT, you cannot make function calls. You must inline
+the functions you will use during early startup, or call compiler
+builtins (__builtin_*).
+
+Without optimizations enabled GNU CC will not inline functions. The
+early startup of the dynamic loader will make function calls via an
+unrelocated PLT and crash. 
+
+Without auditing the dynamic linker code it would be difficult to remove
+this requirement. 
+
+Another reason is that nested functions must be inlined in many cases to
+avoid executable stacks.
+
+In practice there is no reason to compile without optimizations, therefore
+we require that GNU libc be compiled with optimizations enabled.
 
 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
@@ -1957,6 +1986,7 @@
 {AO} Alexandre Oliva, <aoliva@xxxxxxxxxx>
 {BH} Bruno Haible, <haible@xxxxxxxxxxxxxx>
 {SM} Steven Munroe, <sjmunroe@xxxxxxxxxx>
+{CO} Carlos O'Donell, <carlos@xxxxxxxxxxxxxxxx>
 
 Local Variables:
  mode:outline

Modified: fsf/trunk/libc/FAQ.in
==============================================================================
--- fsf/trunk/libc/FAQ.in (original)
+++ fsf/trunk/libc/FAQ.in Sat Feb 23 00:08:59 2008
@@ -386,6 +386,31 @@
 yourself. Please remember that for each architecture there may be various
 patches required to get glibc HEAD into a runnable state. The best course
 of action is to determine if you have all the required patches.
+
+??	Why do I get:
+	`#error "glibc cannot be compiled without optimization"',
+	when trying to compile GNU libc with GNU CC?
+
+{AJ,CO} There are a couple of reasons why the GNU C library will not work
+correctly if it is not complied with optimzation.
+
+In the early startup of the dynamic loader (_dl_start), before
+relocation of the PLT, you cannot make function calls. You must inline
+the functions you will use during early startup, or call compiler
+builtins (__builtin_*).
+
+Without optimizations enabled GNU CC will not inline functions. The
+early startup of the dynamic loader will make function calls via an
+unrelocated PLT and crash. 
+
+Without auditing the dynamic linker code it would be difficult to remove
+this requirement. 
+
+Another reason is that nested functions must be inlined in many cases to
+avoid executable stacks.
+
+In practice there is no reason to compile without optimizations, therefore
+we require that GNU libc be compiled with optimizations enabled.
 
 ? Installation and configuration issues
 
@@ -1685,6 +1710,7 @@
 {AO} Alexandre Oliva, <aoliva@xxxxxxxxxx>
 {BH} Bruno Haible, <haible@xxxxxxxxxxxxxx>
 {SM} Steven Munroe, <sjmunroe@xxxxxxxxxx>
+{CO} Carlos O'Donell, <carlos@xxxxxxxxxxxxxxxx>
 
 Local Variables:
  mode:outline