kumquat-buildroot/package/gcc/6.3.0/892-libgcc-mkmap-symver-support-skip_underscore.patch
Gustavo Zacarias be1a3a3e46 gcc: bump 6.x series to version 6.3.0
Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2016-12-21 17:19:58 +01:00

61 lines
2.2 KiB
Diff

From ae9c3e354440c4a0f105a9eabfb2f77be085ebc1 Mon Sep 17 00:00:00 2001
From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Date: Thu, 18 Aug 2016 17:59:16 +0200
Subject: [PATCH] libgcc/mkmap-symver: support skip_underscore
Some platforms, such as Blackfin, have a special prefix for assembly
symbols as opposed to C symbols. For this reason, a function named
"foo()" in C will in fact be visible as a symbol called "_foo" in the
ELF binary.
The current linker version script logic in libgcc doesn't take into
account this situation properly. The Blackfin specific
libgcc/config/bfin/libgcc-glibc.ver has an additional "_" in front of
every symbol so that it matches the output of "nm" (which gets parsed to
produce the final linker version script). But due to this additional
"_", ld no longer matches with the symbols since "ld" does the matching
with the original symbol name, not the one prefixed with "_".
Due to this, none of the symbols in libgcc/config/bfin/libgcc-glibc.ver
are actually matched with symbols in libgcc. This causes all libgcc
symbols to be left as "LOCAL", which causes lots of "undefined
reference" whenever some C or C++ code that calls a function of libgcc
is compiled.
To address this, this commit introduces a "skip_underscore" variable to
the mkmap-symver script. It tells mkmap-symver to ignore the leading
underscore from the "nm" output.
Note that this new argument is different from the existing
"leading_underscore" argument, which *adds* an additional underscore to
the generated linker version script.
Having this functionality paves the way to using the generic linker
version information for Blackfin, instead of using a custom one.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
libgcc/mkmap-symver.awk | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/libgcc/mkmap-symver.awk b/libgcc/mkmap-symver.awk
index 266832a..30bb179 100644
--- a/libgcc/mkmap-symver.awk
+++ b/libgcc/mkmap-symver.awk
@@ -47,7 +47,11 @@ state == "nm" && ($1 == "U" || $2 == "U") {
state == "nm" && NF == 3 {
split ($3, s, "@")
- def[s[1]] = 1;
+ if (skip_underscore)
+ symname = substr(s[1], 2);
+ else
+ symname = s[1];
+ def[symname] = 1;
sawsymbol = 1;
next;
}
--
2.7.4