diff options
Diffstat (limited to 'meta-networking/recipes-connectivity/openthread/ot-daemon/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch')
| -rw-r--r-- | meta-networking/recipes-connectivity/openthread/ot-daemon/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/meta-networking/recipes-connectivity/openthread/ot-daemon/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch b/meta-networking/recipes-connectivity/openthread/ot-daemon/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch new file mode 100644 index 0000000000..c9edb0098b --- /dev/null +++ b/meta-networking/recipes-connectivity/openthread/ot-daemon/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch @@ -0,0 +1,68 @@ +From c0546e351f6d7ab50eb1de8cef1d0d167760fccc Mon Sep 17 00:00:00 2001 +From: Peter Korsgaard <peter@korsgaard.com> +Date: Mon, 27 Aug 2018 22:50:57 +0200 +Subject: [PATCH] bn_mul.h: fix x86 PIC inline ASM compilation with GCC < 5 +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Fixes #1910 + +With ebx added to the MULADDC_STOP clobber list to fix #1550, the inline +assembly fails to build with GCC < 5 in PIC mode with the following error: + +include/mbedtls/bn_mul.h:46:13: error: PIC register clobbered by ‘ebx’ in ‘asm’ + +This is because older GCC versions treated the x86 ebx register (which is +used for the GOT) as a fixed reserved register when building as PIC. + +This is fixed by an improved register allocator in GCC 5+. From the release +notes: + +Register allocation improvements: Reuse of the PIC hard register, instead of +using a fixed register, was implemented on x86/x86-64 targets. This +improves generated PIC code performance as more hard registers can be used. + +https://www.gnu.org/software/gcc/gcc-5/changes.html + +As a workaround, detect this situation and disable the inline assembly, +similar to the MULADDC_CANNOT_USE_R7 logic. + +Upstream-Status: Backport [https://github.com/Mbed-TLS/mbedtls/commit/c0546e351f6d7ab50eb1de8cef1d0d167760fccc] +Signed-off-by: Peter Korsgaard <peter@korsgaard.com> +--- + library/bn_mul.h | 18 +++++++++++++++++- + 1 file changed, 17 insertions(+), 1 deletion(-) + +--- a/third_party/mbedtls/repo/include/mbedtls/bn_mul.h ++++ b/third_party/mbedtls/repo/include/mbedtls/bn_mul.h +@@ -55,12 +55,28 @@ + ( !defined(__ARMCC_VERSION) || __ARMCC_VERSION >= 6000000 ) + + /* ++ * GCC < 5.0 treated the x86 ebx (which is used for the GOT) as a ++ * fixed reserved register when building as PIC, leading to errors ++ * like: bn_mul.h:46:13: error: PIC register clobbered by 'ebx' in 'asm' ++ * ++ * This is fixed by an improved register allocator in GCC 5+. From the ++ * release notes: ++ * Register allocation improvements: Reuse of the PIC hard register, ++ * instead of using a fixed register, was implemented on x86/x86-64 ++ * targets. This improves generated PIC code performance as more hard ++ * registers can be used. ++ */ ++#if defined(__GNUC__) && __GNUC__ < 5 && defined(__PIC__) ++#define MULADDC_CANNOT_USE_EBX ++#endif ++ ++/* + * Disable use of the i386 assembly code below if option -O0, to disable all + * compiler optimisations, is passed, detected with __OPTIMIZE__ + * This is done as the number of registers used in the assembly code doesn't + * work with the -O0 option. + */ +-#if defined(__i386__) && defined(__OPTIMIZE__) ++#if defined(__i386__) && defined(__OPTIMIZE__) && !defined(MULADDC_CANNOT_USE_EBX) + + #define MULADDC_INIT \ + asm( \ |