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CMake and Static Linking

I’ve managed to solve my problem by using the following: #Dynamic/Shared Libs … #Static start set_target_properties(icarus PROPERTIES LINK_SEARCH_START_STATIC 1) set_target_properties(icarus PROPERTIES LINK_SEARCH_END_STATIC 1) set(CMAKE_FIND_LIBRARY_SUFFIXES “.a”) #Static Libs … #Set Linker flags set(CMAKE_EXE_LINKER_FLAGS “-static-libgcc -static-libstdc++”) This works without passing a -static which creates other big issues, and can essentially mix static and dynamic libraries. As long … Read more

-static option for gcc?

The -static option links a program statically, in other words it does not require a dependency on dynamic libraries at runtime in order to run. To achieve static linking requires that the archive (.a) versions of your libraries exist on the system. so /usr/lib/libc.a, /usr/lib/crt1.o, etc. On modern linux systems (as you are using red … Read more

Makefile removes object files for no reason

The files are being removed because make considers them “intermediate”. When make forms a chain of rules to produce a prerequisite, it treats all files created by the intermediate chains as “intermediate” and removes then when the target is created. See Chained Rules in the manual for GNU make. In your case, you can prevent … Read more

make: *** [ ] Error 1 error [duplicate]

From GNU Make error appendix, as you see this is not a Make error but an error coming from gcc. ‘[foo] Error NN’ ‘[foo] signal description’ These errors are not really make errors at all. They mean that a program that make invoked as part of a recipe returned a non-0 error code (‘Error NN’), … Read more

Why would one use #include_next in a project?

It is used if you want to replace a default header with one of your own making, for example, let’s say you want to replace “stdlib.h”. You would create a file called stdlib.h in your project, and that would be included instead of the default header. #include_next is used if you want to add some … Read more

Why do the addresses in my assembler dump differ from the addresses of registers?

Your GCC makes PIE executables by default, so there is no fixed base address in the file (and disassembly shows it relative to 0, i.e. offsets rather than absolute addresses). Once the kernel’s ELF program loader has created a running process from the executable (and chosen a virtual address as the base), GDB can show … Read more

Errors that refer to a bunch of unresolved OpenSSL symbols that clearly exist?

The problem was caused by the order of the libraries in the link command. Switching the order of libcrypto.a and libssl.a resolved all of the symbols. GCC uses LD by default, and its a single pass linker. When you have two libraries, like libssl and libcrypto linked in a particular order, it means libssl depends … Read more

Why gcc 4.1 + gcov reports 100% branch coverage and newer (4.4, 4.6, 4.8) reports 50% for “p = new class;” line?

Solved ! We have some C/C++ files with and without exceptions handling, so lcov/gcov process “exceptions handling” for each code block. Inside a normal block, for example: int main(void) { … … [+ -] printf(“Hello\n”); … } gcov reports that printf line has a “branch coverage” of 50% —> WHY ? Because exceptions handling is … Read more

How to write multiline inline assembly code in GCC C++?

I always find some examples on Internet that the guy manually insert a tab and new-line instead of \t and \n, however it doesn’t work for me. Not very sure if your example even compile.. but this is how I do: asm volatile( // note the backslash line-continuation “xor %eax,%eax \n\t\ mov $0x7c802446, %ebx \n\t\ … Read more

Why did GCC generate mov %eax,%eax and what does it mean?

In x86-64, 32-bit instructions implicitly zero-extend: bits 32-63 are cleared (to avoid false dependencies). So sometimes that’s why you’ll see odd-looking instructions. (Is mov %esi, %esi a no-op or not on x86-64?) However, in this case the previous mov-load is also 32-bit so the high half of %rax is already cleared. The mov %eax, %eax … Read more