ot-daemon,ot-br-posix: Fix mbedtls module builds

Add a backport to fix build of mbedTLS on x86

Signed-off-by: Khem Raj <raj.khem@gmail.com>

6 files changed, 229 insertions, 2 deletions

diff --git a/meta-networking/recipes-connectivity/openthread/ot-br-posix/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch b/meta-networking/recipes-connectivity/openthread/ot-br-posix/0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch
new file mode 100644
index 000000000..8122e725e
--- /dev/null
+++ b/meta-networking/recipes-connectivity/openthread/ot-br-posix/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/openthread/repo/third_party/mbedtls/repo/include/mbedtls/bn_mul.h
++++ b/third_party/openthread/repo/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(                                    \
diff --git a/meta-networking/recipes-connectivity/openthread/ot-br-posix/mbedtls.patch b/meta-networking/recipes-connectivity/openthread/ot-br-posix/mbedtls.patch
new file mode 100644
index 000000000..91b304648
--- /dev/null
+++ b/meta-networking/recipes-connectivity/openthread/ot-br-posix/mbedtls.patch
@@ -0,0 +1,43 @@
+mbedtls: Disable documentation warning as error with clang
+
+There are shortcomings with doxygen info which clang-15+ flags, dont
+treat them as errors
+
+Remove unused variable
+
+Fixes
+library/bignum.c:1395:29: error: variable 't' set but not used [-Werror,-Wunused-but-set-variable]
+
+Upstream-Status: Pending
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+--- a/third_party/openthread/repo/third_party/mbedtls/repo/library/bignum.c
++++ b/third_party/openthread/repo/third_party/mbedtls/repo/library/bignum.c
+@@ -1544,7 +1544,7 @@ __attribute__ ((noinline))
+ #endif
+ void mpi_mul_hlp( size_t i, mbedtls_mpi_uint *s, mbedtls_mpi_uint *d, mbedtls_mpi_uint b )
+ {
+-    mbedtls_mpi_uint c = 0, t = 0;
++    mbedtls_mpi_uint c = 0;
+ 
+ #if defined(MULADDC_HUIT)
+     for( ; i >= 8; i -= 8 )
+@@ -1595,8 +1595,6 @@ void mpi_mul_hlp( size_t i, mbedtls_mpi_
+     }
+ #endif /* MULADDC_HUIT */
+ 
+-    t++;
+-
+     do {
+         *d += c; c = ( *d < c ); d++;
+     }
+--- a/third_party/openthread/repo/third_party/mbedtls/repo/CMakeLists.txt
++++ b/third_party/openthread/repo/third_party/mbedtls/repo/CMakeLists.txt
+@@ -192,7 +192,7 @@ if(CMAKE_COMPILER_IS_GNU)
+ endif(CMAKE_COMPILER_IS_GNU)
+ 
+ if(CMAKE_COMPILER_IS_CLANG)
+-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Wwrite-strings -Wpointer-arith -Wimplicit-fallthrough -Wshadow -Wvla")
++    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Wwrite-strings -Wpointer-arith -Wimplicit-fallthrough -Wshadow -Wvla -Wno-error=documentation")
+     set(CMAKE_C_FLAGS_RELEASE     "-O2")
+     set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
+     set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")
diff --git a/meta-networking/recipes-connectivity/openthread/ot-br-posix_git.bb b/meta-networking/recipes-connectivity/openthread/ot-br-posix_git.bb
index a16b77849..bbec81c27 100644
--- a/meta-networking/recipes-connectivity/openthread/ot-br-posix_git.bb
+++ b/meta-networking/recipes-connectivity/openthread/ot-br-posix_git.bb
@@ -17,14 +17,17 @@ PV = "0.3.0+git${SRCPV}"
 SRC_URI = "gitsm://github.com/openthread/ot-br-posix.git;protocol=https;branch=main \
            file://0001-otbr-agent.service.in-remove-pre-exec-hook-for-mdns-.patch \
            file://0001-cmake-Disable-nonnull-compare-warning-on-gcc.patch \
+           file://0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch \
+           file://mbedtls.patch \
            "
 
 S = "${WORKDIR}/git"
 SYSTEMD_SERVICE:${PN} = "otbr-agent.service"
 
 inherit pkgconfig cmake systemd
-
-CXXFLAGS:append:libc-musl:toolchain-clang = " -Wno-error=sign-compare"
+# openthread/repo/src/cli/cli.cpp:1786:18: fatal error: variable 'i' set but not used [-Wunused-but-set-variable]
+#    for (uint8_t i = 0;; i++)
+CXXFLAGS:append:libc-musl:toolchain-clang = " -Wno-error=sign-compare -Wno-error=unused-but-set-variable"
 
 EXTRA_OECMAKE = "-DBUILD_TESTING=OFF \
                  -DOTBR_DBUS=ON \
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 000000000..c9edb0098
--- /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(                                    \
diff --git a/meta-networking/recipes-connectivity/openthread/ot-daemon/mbedtls.patch b/meta-networking/recipes-connectivity/openthread/ot-daemon/mbedtls.patch
new file mode 100644
index 000000000..be26a20da
--- /dev/null
+++ b/meta-networking/recipes-connectivity/openthread/ot-daemon/mbedtls.patch
@@ -0,0 +1,43 @@
+mbedtls: Disable documentation warning as error with clang
+
+There are shortcomings with doxygen info which clang-15+ flags, dont
+treat them as errors
+
+Remove unused variable
+
+Fixes
+library/bignum.c:1395:29: error: variable 't' set but not used [-Werror,-Wunused-but-set-variable]
+
+Upstream-Status: Pending
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+--- a/third_party/mbedtls/repo/library/bignum.c
++++ b/third_party/mbedtls/repo/library/bignum.c
+@@ -1544,7 +1544,7 @@ __attribute__ ((noinline))
+ #endif
+ void mpi_mul_hlp( size_t i, mbedtls_mpi_uint *s, mbedtls_mpi_uint *d, mbedtls_mpi_uint b )
+ {
+-    mbedtls_mpi_uint c = 0, t = 0;
++    mbedtls_mpi_uint c = 0;
+ 
+ #if defined(MULADDC_HUIT)
+     for( ; i >= 8; i -= 8 )
+@@ -1595,8 +1595,6 @@ void mpi_mul_hlp( size_t i, mbedtls_mpi_
+     }
+ #endif /* MULADDC_HUIT */
+ 
+-    t++;
+-
+     do {
+         *d += c; c = ( *d < c ); d++;
+     }
+--- a/third_party/mbedtls/repo/CMakeLists.txt
++++ b/third_party/mbedtls/repo/CMakeLists.txt
+@@ -192,7 +192,7 @@ if(CMAKE_COMPILER_IS_GNU)
+ endif(CMAKE_COMPILER_IS_GNU)
+ 
+ if(CMAKE_COMPILER_IS_CLANG)
+-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Wwrite-strings -Wpointer-arith -Wimplicit-fallthrough -Wshadow -Wvla")
++    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Wwrite-strings -Wpointer-arith -Wimplicit-fallthrough -Wshadow -Wvla -Wno-error=documentation")
+     set(CMAKE_C_FLAGS_RELEASE     "-O2")
+     set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
+     set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")
diff --git a/meta-networking/recipes-connectivity/openthread/ot-daemon_git.bb b/meta-networking/recipes-connectivity/openthread/ot-daemon_git.bb
index f3f4c70fa..18703d6c4 100644
--- a/meta-networking/recipes-connectivity/openthread/ot-daemon_git.bb
+++ b/meta-networking/recipes-connectivity/openthread/ot-daemon_git.bb
@@ -12,6 +12,8 @@ SRCREV = "7dfde1f12923f03c9680be4d838b94b7a2320324"
 PV = "0.1+git${SRCPV}"
 
 SRC_URI = "git://github.com/openthread/openthread.git;protocol=https;branch=main \
+           file://0001-bn_mul.h-fix-x86-PIC-inline-ASM-compilation-with-GCC.patch \
+           file://mbedtls.patch \
            "
 
 S = "${WORKDIR}/git"