| Message ID | 20240105191710.1330461-1-abrodkin@synopsys.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2] arch: Set max/common-page-size for libgcc & libstdc++ | expand |
On Fri, 5 Jan 2024 11:17:10 -0800 Alexey Brodkin via buildroot <buildroot@buildroot.org> wrote: > With [1], [2] & [3] we made sure Buildroot packages get built with > proper MMU page size assumed. This was done nicely through insertion of > required flags into the toolchain wrapper so that there's no need to > pass these flags to each and every package separately - toolchain > wrapper used for real building has all set internally and so proper > flags are impleicitly used. > > But there's yet another corner case which is not handled that way - > these are binaries or rather libraries which are being used as a part of > GCC compilation: libgcc_s.so.1 and libstdc++.so. > > And so to make sure both the libraries get built properly we need to set > TARGET_CFLAGS (cures libgcc_s.so) & TARGET_LDFLAGS (cures libstdc++.so). > > In case of ARM by defaut 64 KiB page size seems to be used, as w/o that > patch I see the following for BR2_ARM64_PAGE_SIZE_4K=y: > --------------------------->8---------------------------- > $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/lib/libgcc_s.so.1 Applied to master with a few minor improvements in the commit title and commit log. Thanks a lot! Thomas
>>>>> "Alexey" == Alexey Brodkin via buildroot <buildroot@buildroot.org> writes: > With [1], [2] & [3] we made sure Buildroot packages get built with > proper MMU page size assumed. This was done nicely through insertion of > required flags into the toolchain wrapper so that there's no need to > pass these flags to each and every package separately - toolchain > wrapper used for real building has all set internally and so proper > flags are impleicitly used. > But there's yet another corner case which is not handled that way - > these are binaries or rather libraries which are being used as a part of > GCC compilation: libgcc_s.so.1 and libstdc++.so. > And so to make sure both the libraries get built properly we need to set > TARGET_CFLAGS (cures libgcc_s.so) & TARGET_LDFLAGS (cures libstdc++.so). > In case of ARM by defaut 64 KiB page size seems to be used, as w/o that > patch I see the following for BR2_ARM64_PAGE_SIZE_4K=y: ---------------------------> 8---------------------------- > $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/lib/libgcc_s.so.1 > Elf file type is DYN (Shared object file) > Entry point 0x0 > There are 6 program headers, starting at offset 64 > Program Headers: > Type Offset VirtAddr PhysAddr > FileSiz MemSiz Flags Align > LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 > 0x0000000000013d1c 0x0000000000013d1c R E 0x10000 > LOAD 0x000000000001fd98 0x000000000002fd98 0x000000000002fd98 > 0x0000000000000438 0x00000000000005c8 RW 0x10000 > DYNAMIC 0x000000000001fdb8 0x000000000002fdb8 0x000000000002fdb8 > 0x0000000000000200 0x0000000000000200 RW 0x8 > $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/usr/lib/libstdc++.so.6.0.32 > Elf file type is DYN (Shared object file) > Entry point 0x0 > There are 7 program headers, starting at offset 64 > Program Headers: > Type Offset VirtAddr PhysAddr > FileSiz MemSiz Flags Align > LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 > 0x00000000001d3462 0x00000000001d3462 R E 0x10000 > LOAD 0x00000000001d5760 0x00000000001e5760 0x00000000001e5760 > 0x000000000000e528 0x0000000000012de8 RW 0x10000 > DYNAMIC 0x00000000001deef0 0x00000000001eeef0 0x00000000001eeef0 > 0x0000000000000240 0x0000000000000240 RW 0x8 ---------------------------> 8---------------------------- > Note alignment of 0x10000 in sections marked for loading. > And with the patch applied we get expected alignment of 0x1000 (4 KiB): ---------------------------> 8---------------------------- > $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/lib/libgcc_s.so.1 > Elf file type is DYN (Shared object file) > Entry point 0x0 > There are 6 program headers, starting at offset 64 > Program Headers: > Type Offset VirtAddr PhysAddr > FileSiz MemSiz Flags Align > LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 > 0x0000000000013d1c 0x0000000000013d1c R E 0x1000 > LOAD 0x0000000000013d98 0x0000000000014d98 0x0000000000014d98 > 0x0000000000000438 0x00000000000005c8 RW 0x1000 > DYNAMIC 0x0000000000013db8 0x0000000000014db8 0x0000000000014db8 > 0x0000000000000200 0x0000000000000200 RW 0x8 > $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/usr/lib/libstdc++.so.6.0.32 > Elf file type is DYN (Shared object file) > Entry point 0x0 > There are 7 program headers, starting at offset 64 > Program Headers: > Type Offset VirtAddr PhysAddr > FileSiz MemSiz Flags Align > LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 > 0x00000000001d3462 0x00000000001d3462 R E 0x1000 > LOAD 0x00000000001d3760 0x00000000001d4760 0x00000000001d4760 > 0x000000000000e528 0x0000000000012de8 RW 0x1000 > DYNAMIC 0x00000000001dcef0 0x00000000001ddef0 0x00000000001ddef0 > 0x0000000000000240 0x0000000000000240 RW 0x8 ---------------------------> 8---------------------------- > What's nice, we're getting rid of a special handling of "-matomic" > as it's already a part of ARCH_TOOLCHAIN_WRAPPER_OPTS. > [1] https://git.buildroot.net/buildroot/commit/?id=3cc2c6d19ab2e1bb4634f26f9318da9b07df5fff > [2] https://git.buildroot.net/buildroot/commit/?id=dcb74db89e74e512e36b32cea6f574a1a1ca84c4 > [3] https://git.buildroot.net/buildroot/commit/?id=5e52c28397b79f8c4c99552217cbe95202166626 > Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> > Signed-off-by: Vladimir Isaev <VVIsaev@gmail.com> > Signed-off-by: Pavel Kozlov <kozlov@synopsys.com> > Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com> > Cc: Yann E. MORIN <yann.morin.1998@free.fr> > Cc: Arnout Vandecappelle <arnout@mind.be> > --- > Changes in v2: > * Instead of setting TARGET_{C|LD}FLAGS use > ARCH_TOOLCHAIN_WRAPPER_OPTS for configuring GCC. Committed to 2023.02.x and 2023.11.x, thanks.
diff --git a/package/gcc/gcc.mk b/package/gcc/gcc.mk index 93bc46643c..94935d79a2 100644 --- a/package/gcc/gcc.mk +++ b/package/gcc/gcc.mk @@ -98,23 +98,24 @@ HOST_GCC_COMMON_CONF_ENV = \ HOST_GCC_COMMON_MAKE_OPTS = \ gcc_cv_prog_makeinfo_modern=no -GCC_COMMON_TARGET_CFLAGS = $(TARGET_CFLAGS) -GCC_COMMON_TARGET_CXXFLAGS = $(TARGET_CXXFLAGS) +# Target binaries and libraries which are being built as a part of GCC +# don't use Buildroot toolchain wrapper because, instead its very own "xgcc" +# binary is used. And so we need to explicitly propagate ALL the flags +# directly to "xgcc" and that is done via configure-time environment +# variables, see below setup of HOST_GCC_COMMON_CONF_ENV. +GCC_COMMON_TARGET_CFLAGS = $(TARGET_CFLAGS) $(ARCH_TOOLCHAIN_WRAPPER_OPTS) +GCC_COMMON_TARGET_CXXFLAGS = $(TARGET_CXXFLAGS) $(ARCH_TOOLCHAIN_WRAPPER_OPTS) +GCC_COMMON_TARGET_LDFLAGS = $(TARGET_LDFLAGS) $(ARCH_TOOLCHAIN_WRAPPER_OPTS) # used to fix ../../../../libsanitizer/libbacktrace/../../libbacktrace/elf.c:772:21: error: 'st.st_mode' may be used uninitialized in this function [-Werror=maybe-uninitialized] ifeq ($(BR2_ENABLE_DEBUG),y) GCC_COMMON_TARGET_CFLAGS += -Wno-error endif -# Make sure libgcc & libstdc++ always get built with -matomic on ARC700 -ifeq ($(GCC_TARGET_CPU):$(BR2_ARC_ATOMIC_EXT),arc700:y) -GCC_COMMON_TARGET_CFLAGS += -matomic -GCC_COMMON_TARGET_CXXFLAGS += -matomic -endif - # Propagate options used for target software building to GCC target libs HOST_GCC_COMMON_CONF_ENV += CFLAGS_FOR_TARGET="$(GCC_COMMON_TARGET_CFLAGS)" HOST_GCC_COMMON_CONF_ENV += CXXFLAGS_FOR_TARGET="$(GCC_COMMON_TARGET_CXXFLAGS)" +HOST_GCC_COMMON_CONF_ENV += LDFLAGS_FOR_TARGET="$(GCC_COMMON_TARGET_LDFLAGS)" HOST_GCC_COMMON_CONF_ENV += AR_FOR_TARGET=gcc-ar NM_FOR_TARGET=gcc-nm RANLIB_FOR_TARGET=gcc-ranlib # libitm needs sparc V9+
With [1], [2] & [3] we made sure Buildroot packages get built with proper MMU page size assumed. This was done nicely through insertion of required flags into the toolchain wrapper so that there's no need to pass these flags to each and every package separately - toolchain wrapper used for real building has all set internally and so proper flags are impleicitly used. But there's yet another corner case which is not handled that way - these are binaries or rather libraries which are being used as a part of GCC compilation: libgcc_s.so.1 and libstdc++.so. And so to make sure both the libraries get built properly we need to set TARGET_CFLAGS (cures libgcc_s.so) & TARGET_LDFLAGS (cures libstdc++.so). In case of ARM by defaut 64 KiB page size seems to be used, as w/o that patch I see the following for BR2_ARM64_PAGE_SIZE_4K=y: --------------------------->8---------------------------- $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/lib/libgcc_s.so.1 Elf file type is DYN (Shared object file) Entry point 0x0 There are 6 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000013d1c 0x0000000000013d1c R E 0x10000 LOAD 0x000000000001fd98 0x000000000002fd98 0x000000000002fd98 0x0000000000000438 0x00000000000005c8 RW 0x10000 DYNAMIC 0x000000000001fdb8 0x000000000002fdb8 0x000000000002fdb8 0x0000000000000200 0x0000000000000200 RW 0x8 $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/usr/lib/libstdc++.so.6.0.32 Elf file type is DYN (Shared object file) Entry point 0x0 There are 7 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x00000000001d3462 0x00000000001d3462 R E 0x10000 LOAD 0x00000000001d5760 0x00000000001e5760 0x00000000001e5760 0x000000000000e528 0x0000000000012de8 RW 0x10000 DYNAMIC 0x00000000001deef0 0x00000000001eeef0 0x00000000001eeef0 0x0000000000000240 0x0000000000000240 RW 0x8 --------------------------->8---------------------------- Note alignment of 0x10000 in sections marked for loading. And with the patch applied we get expected alignment of 0x1000 (4 KiB): --------------------------->8---------------------------- $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/lib/libgcc_s.so.1 Elf file type is DYN (Shared object file) Entry point 0x0 There are 6 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000013d1c 0x0000000000013d1c R E 0x1000 LOAD 0x0000000000013d98 0x0000000000014d98 0x0000000000014d98 0x0000000000000438 0x00000000000005c8 RW 0x1000 DYNAMIC 0x0000000000013db8 0x0000000000014db8 0x0000000000014db8 0x0000000000000200 0x0000000000000200 RW 0x8 $ ./output/host/bin/aarch64-linux-readelf -l ./output/target/usr/lib/libstdc++.so.6.0.32 Elf file type is DYN (Shared object file) Entry point 0x0 There are 7 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align LOAD 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x00000000001d3462 0x00000000001d3462 R E 0x1000 LOAD 0x00000000001d3760 0x00000000001d4760 0x00000000001d4760 0x000000000000e528 0x0000000000012de8 RW 0x1000 DYNAMIC 0x00000000001dcef0 0x00000000001ddef0 0x00000000001ddef0 0x0000000000000240 0x0000000000000240 RW 0x8 --------------------------->8---------------------------- What's nice, we're getting rid of a special handling of "-matomic" as it's already a part of ARCH_TOOLCHAIN_WRAPPER_OPTS. [1] https://git.buildroot.net/buildroot/commit/?id=3cc2c6d19ab2e1bb4634f26f9318da9b07df5fff [2] https://git.buildroot.net/buildroot/commit/?id=dcb74db89e74e512e36b32cea6f574a1a1ca84c4 [3] https://git.buildroot.net/buildroot/commit/?id=5e52c28397b79f8c4c99552217cbe95202166626 Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vladimir Isaev <VVIsaev@gmail.com> Signed-off-by: Pavel Kozlov <kozlov@synopsys.com> Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Cc: Yann E. MORIN <yann.morin.1998@free.fr> Cc: Arnout Vandecappelle <arnout@mind.be> --- Changes in v2: * Instead of setting TARGET_{C|LD}FLAGS use ARCH_TOOLCHAIN_WRAPPER_OPTS for configuring GCC. package/gcc/gcc.mk | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-)