patches/gcc/4.3.1/110-trampolinewarn.patch
author "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Sat Jan 31 17:49:27 2009 +0000 (2009-01-31)
changeset 1183 268544004e77
parent 746 b150d6f590fc
permissions -rw-r--r--
On 20090131.1659+0100, Vincent Sanders <vince@kyllikki.org> wrote:
[This]patch is a bit more involved. The patch addresses a gcc
regression in the 4.3 series (specifically this patch is against 4.3.2
which does *not* have a lot of other issues which affect kernel building)

GCC bug tracker has this issue as
#38453 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38453
#32044 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32044

comment 65 of #32044 has the fix being applied to gcc trunk as revision #142719

The attached patch is a backport to gcc 4.3.2 which allows this
version to be used to generate correct output for various ARM kernel
build (and indeed is teh correct answer in general).

/trunk/patches/gcc/4.3.2/360-fix-expensive-optimize.patch | 207 207 0 0 +++++++++++++++++++++
1 file changed, 207 insertions(+)
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Original patch from gentoo: gentoo/src/patchsets/gcc/4.3.1/gentoo/00_all_gcc-trampolinewarn.patch
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	This trivial patch causes gcc to emit a warning whenever
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	it generates a trampoline.  These are otherwise hard to
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	locate.  It is rigged to default ON - to have it default
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	to OFF remove the text 'Init(1)' from the common.opt
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	patch, leaving just 'Common Var(warn_trampolines)'.
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	Kevin F. Quinn <kevquinn@gentoo.org> 17 Jan 2006
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diff -durN gcc-4.3.1.orig/gcc/builtins.c gcc-4.3.1/gcc/builtins.c
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--- gcc-4.3.1.orig/gcc/builtins.c	2008-04-23 00:36:27.000000000 +0200
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+++ gcc-4.3.1/gcc/builtins.c	2008-06-10 14:56:54.000000000 +0200
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@@ -5662,6 +5662,9 @@
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   trampolines_created = 1;
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   INITIALIZE_TRAMPOLINE (r_tramp, r_func, r_chain);
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+  if (warn_trampolines)
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+    warning (OPT_Wtrampolines, "generating trampoline in object (requires executable stack)");
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+
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   return const0_rtx;
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 }
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diff -durN gcc-4.3.1.orig/gcc/common.opt gcc-4.3.1/gcc/common.opt
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--- gcc-4.3.1.orig/gcc/common.opt	2008-01-22 15:11:44.000000000 +0100
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+++ gcc-4.3.1/gcc/common.opt	2008-06-10 14:56:54.000000000 +0200
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@@ -182,6 +182,10 @@
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 Common Var(warn_system_headers) Warning
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 Do not suppress warnings from system headers
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+Wtrampolines
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+Common Var(warn_trampolines) Init(1)
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+Warn whenever a trampoline is generated
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+
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 Wuninitialized
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 Common Var(warn_uninitialized) Warning
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 Warn about uninitialized automatic variables