From 55171f2930be98c8a49991435cdf3a8b574353b6 Mon Sep 17 00:00:00 2001 From: Anton Protopopov Date: Thu, 22 Dec 2022 10:26:27 +0000 Subject: bpftool: Fix linkage with statically built libllvm Since the commit eb9d1acf634b ("bpftool: Add LLVM as default library for disassembling JIT-ed programs") we might link the bpftool program with the libllvm library. This works fine when a shared libllvm library is available, but fails if we want to link bpftool with a statically built LLVM: [...] /usr/bin/ld: /usr/local/lib/libLLVMSupport.a(CrashRecoveryContext.cpp.o): in function `llvm::CrashRecoveryContextCleanup::~CrashRecoveryContextCleanup()': CrashRecoveryContext.cpp:(.text._ZN4llvm27CrashRecoveryContextCleanupD0Ev+0x17): undefined reference to `operator delete(void*, unsigned long)' /usr/bin/ld: /usr/local/lib/libLLVMSupport.a(CrashRecoveryContext.cpp.o): in function `llvm::CrashRecoveryContext::~CrashRecoveryContext()': CrashRecoveryContext.cpp:(.text._ZN4llvm20CrashRecoveryContextD2Ev+0xc8): undefined reference to `operator delete(void*, unsigned long)' [...] So in the case of static libllvm we need to explicitly link bpftool with required libraries, namely, libstdc++ and those provided by the `llvm-config --system-libs` command. We can distinguish between the shared and static cases by using the `llvm-config --shared-mode` command. Fixes: eb9d1acf634b ("bpftool: Add LLVM as default library for disassembling JIT-ed programs") Signed-off-by: Anton Protopopov Signed-off-by: Daniel Borkmann Acked-by: Stanislav Fomichev Link: https://lore.kernel.org/bpf/20221222102627.1643709-1-aspsk@isovalent.com --- tools/bpf/bpftool/Makefile | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'tools') diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index 787b857d3fb5..f610e184ce02 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -145,6 +145,10 @@ ifeq ($(feature-llvm),1) LLVM_CONFIG_LIB_COMPONENTS := mcdisassembler all-targets CFLAGS += $(shell $(LLVM_CONFIG) --cflags --libs $(LLVM_CONFIG_LIB_COMPONENTS)) LIBS += $(shell $(LLVM_CONFIG) --libs $(LLVM_CONFIG_LIB_COMPONENTS)) + ifeq ($(shell $(LLVM_CONFIG) --shared-mode),static) + LIBS += $(shell $(LLVM_CONFIG) --system-libs $(LLVM_CONFIG_LIB_COMPONENTS)) + LIBS += -lstdc++ + endif LDFLAGS += $(shell $(LLVM_CONFIG) --ldflags) else # Fall back on libbfd -- cgit v1.2.3