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GCC QUESTIONS

Can you explain why gcc -S output something like assemble?
Can you explain why gcc -S output something like assemble?
like below fixes the issue A good explanation of the compiling and linking concepts is here.Also, see this SO thread (difference between compiling and linking).
TAG : gcc
Date : November 14 2020, 07:01 PM , By : Miguel Ángel Rojas
What is the use of "push %ebp; movl %esp, %ebp" generated by GCC for x86?
What is the use of "push %ebp; movl %esp, %ebp" generated by GCC for x86?
help you fix your problem unwind's explanation is the literal truth (one minor directional error notwithstanding), but doesn't explain why.%ebp is the "base pointer" for your stack frame. It's the pointer used by the C runtime to access local variabl
TAG : gcc
Date : November 11 2020, 07:00 PM , By : TGxPatriot
How do I edit error messages in GCC source
How do I edit error messages in GCC source
like below fixes the issue GCC is already localized. You don't need to edit any source, just edit (or create, if it doesn't exist) the proper po file. Getting it into the official distribution seems to require accepting the GNU license (not very surp
TAG : gcc
Date : November 08 2020, 07:01 PM , By : user3857640
How to link libs once only in GCC?
How to link libs once only in GCC?
This might help you Pardon my question, I am a beginner to GCC. I have a framework project that holds source code for multiple subcomponents. , Object files (.o) are created by compilation commands, e.g.
TAG : gcc
Date : October 15 2020, 06:10 AM , By : Divad
error: operand must be a register in range [d0, d15]
error: operand must be a register in range [d0, d15]
wish helps you For vector-scalar multiplications, the 32bit scalar container must be d0 - d15 by definition. (It's d0 - d7 for 16bit scalars)It's a physical limitation, and the VTBL instructions behave similarly.
TAG : gcc
Date : October 14 2020, 02:00 AM , By : galley
How to make GCC enforce pure/const attribute?
How to make GCC enforce pure/const attribute?
I hope this helps . GCC manual says that __attribute__((const)) is used by the programmer to indicate the behavior of the function so that it can be optimized better.
TAG : gcc
Date : October 13 2020, 09:00 AM , By : Firefly_111
Where is __builtin_va_start defined?
Where is __builtin_va_start defined?
hope this fix your issue That __builtin_va_start is not defined anywhere. It is a GCC compiler builtin (a bit like sizeof is a compile-time operator). It is an implementation detail related to the standard header (provided by the compiler, not the C
TAG : gcc
Date : October 12 2020, 02:00 PM , By : Beil Zheng
How to manually add debug type information to a GNU GAS assembly "array" symbol?
How to manually add debug type information to a GNU GAS assembly "array" symbol?
Any of those help I am no DWARF expert either, but poking around with dwarfdump reveals enough to answer the question.
TAG : gcc
Date : October 10 2020, 08:00 PM , By : V.M
What does this backslash do in this assembly code?
What does this backslash do in this assembly code?
Does that help Inside a GAS .macro, you use \foo to refer to a macro parameter called foo.The .macro you're looking at has 3 args with default values; presumably in some use-case they want to get alternate values saved in place of what's actually in
TAG : gcc
Date : October 10 2020, 06:00 PM , By : Matthew Hughes
My compiled GNU GCC 9 in Solaris 10 SPARC is not working
My compiled GNU GCC 9 in Solaris 10 SPARC is not working
Any of those help cc1 (the compiler proper executable) depends on the dynamic libmpc.so.3 library. See
TAG : gcc
Date : October 10 2020, 10:00 AM , By : user6035298
Understanding gcc behaviour regarding AAPCS (on STM32)
Understanding gcc behaviour regarding AAPCS (on STM32)
With these it helps You can't just open an inline assembly block and assume that r0 and r1 still contain the function arguments. There is no guarantee for that whatsoever. If you need to use the arguments you need to pass them properly as input and o
TAG : gcc
Date : October 10 2020, 05:00 AM , By : Corram
SFINAE fails with template non-type reference argument
SFINAE fails with template non-type reference argument
will help you Consider this code: , Maybe instead of auto you want decltype(auto):
TAG : gcc
Date : October 08 2020, 12:00 PM , By : cktricky
Unresolved external function while linking Ocaml and C
Unresolved external function while linking Ocaml and C
Any of those help Generally you have to list modules in "topological" order. I.e., you need to list a module before the other modules that use it. I will test to see if this solves your problem.Update
TAG : gcc
Date : October 08 2020, 11:00 AM , By : Alexander Vega
Understanding GCC inline assembly code that uses memory source operands and x87 fcomi / fcmov
Understanding GCC inline assembly code that uses memory source operands and x87 fcomi / fcmov
this one helps. You probably want to replace this inline asm instead of even trying to fix and/or improve it. You mentioned something about "secure", so many non-data-dependent performance to avoid timing side channels? You might want to ensure branc
TAG : gcc
Date : October 07 2020, 06:00 PM , By : Roger Noguera
Different function call assemblywith -O0 and -O1 with GCC on ARM
Different function call assemblywith -O0 and -O1 with GCC on ARM
I wish did fix the issue. Don't bother analyzing machine codes compiled for the debug mode, because they follow some very obscured sequences that allows step by step execution by breakpoints while keeping all the global/local variables visible.It isn
TAG : gcc
Date : October 07 2020, 06:00 PM , By : Jean-Marie D'Heur
Generated assembly for extended alignment of stack variables
Generated assembly for extended alignment of stack variables
will help you I was digging into the assembly of code that was using extended alignment for a stack-based variable. This is a smaller version of the code , Nothing magical here. Line-by-line:
TAG : gcc
Date : October 06 2020, 06:00 PM , By : CDEW
inline assembly code to read/write XMM & YMM registers?
inline assembly code to read/write XMM & YMM registers?
this will help The first step is to include , which includes all the definitions for the needed types as well as all the Intel Intrinsics for accessing all the MMX/SSE/AVX instructions. For most purposes, you want to use those intrinsics and not inli
TAG : gcc
Date : October 06 2020, 03:00 PM , By : Abhinav
gnatmake -o flag produces incorrect object file name
gnatmake -o flag produces incorrect object file name
hop of those help? For gnatmake, -o 'chooses an alternate executable name'. But even using gcc (or g++) on its own fails, at any rate on macOS, because gnat1: incorrect object file name.I found that you can compile to assembler and then compile that.
TAG : gcc
Date : October 06 2020, 07:00 AM , By : helloth3r3
Why is private move constructor allowed while initalizing via static method?
Why is private move constructor allowed while initalizing via static method?
I hope this helps . I believe this is a consequence of P0135: Wording for guaranteed copy elision through simplified value categories, specifically the change to [dcl.init]: If the initializer expression is a prvalue and the cv-unqualified version of
TAG : gcc
Date : October 06 2020, 03:00 AM , By : npsnps
Change GCC's output for 0-set (clear) operation
Change GCC's output for 0-set (clear) operation
Any of those help You mean like sub eax,eax which is specially recognized as a zeroing idiom on only some CPUs, not all?The optimization is done as part of -fpeephole2, as part of -O2 or -Os; using -fno-peephole2 would give you mov eax,0 for material
TAG : gcc
Date : October 05 2020, 02:00 PM , By : jkwhitman
Why does GCC for Risc-V generate nop instructions after call
Why does GCC for Risc-V generate nop instructions after call
Hope that helps Not a complete answer, but at least an attempt at diving into the reason why the nop appears. I strongly believe it's a bug/leftover from architectures that have delay slots (as it gets added in the very first RTL pass - expand).Onto
TAG : gcc
Date : October 04 2020, 04:00 AM , By : Cristi L
Could someone please explain what this inline #define assembly is doing?
Could someone please explain what this inline #define assembly is doing?
should help you out The first two instructions add dst and src together, storing the result in the accumulator. The third instruction computes what's sometimes called the "end-around carry" and the fourth stores the result in dst.The following is an
TAG : gcc
Date : October 03 2020, 07:00 AM , By : Benjamin Pele
Why does gcc generates strange code without flag -fno-pie?
Why does gcc generates strange code without flag -fno-pie?
Hope that helps You disassembled the object file without the --reloc flag, so the output is misleading. With the --reloc flag, you'll see this:
TAG : gcc
Date : October 03 2020, 07:00 AM , By : shahzad
ANTLR4 Grammar for parsing x86 Assembly
ANTLR4 Grammar for parsing x86 Assembly
will be helpful for those in need Reading that grammar, and looking and the AST generated, it's easy to see that a line like .p2align 4,,15 is matching the rule lbl for the token .p2align and that then 4,,15 doesn't match any assemblydirective or ins
TAG : gcc
Date : October 02 2020, 05:00 PM , By : Sajid
Loading variable addresses into registers PowerPC inline Assembly
Loading variable addresses into registers PowerPC inline Assembly
fixed the issue. Will look into that further It's not clear what you are trying to do with the initial instructions:
TAG : gcc
Date : October 01 2020, 12:00 AM , By : Puthiyavan S
What C instructions do I need to use to get gcc's x86-64 autovectorizer to output pshufb opcodes?
What C instructions do I need to use to get gcc's x86-64 autovectorizer to output pshufb opcodes?
To fix this issue I doubt that pshufb will be the most efficient solution, unless you intend to have the result in the lower part of an xmm register. If you do, provide an actual usage example.If you write something like:
TAG : gcc
Date : September 29 2020, 10:00 AM , By : Anuhjean
What is linker, compiler, assembler and elaborator in an IDE like CodeBlocks?
What is linker, compiler, assembler and elaborator in an IDE like CodeBlocks?
This might help you A compiler and an assembler take as input source code and produce object code files in machine language (the binary form of the CPU instructions). The main difference is that a compiler takes source code written in a high level la
TAG : gcc
Date : September 28 2020, 02:00 PM , By : user6074726
gcc assembler - create only the minimal instructions necessary
gcc assembler - create only the minimal instructions necessary
hope this fix your issue GCC automatically links the C / C++ runtime start-up crt0.o and the standard library. You can provide your own startup code to override the default and provide command line options to force it not to link no the standard libr
TAG : gcc
Date : September 28 2020, 10:00 AM , By : Postal
How to pass arguments to inline GCC/Clang asembly with Intel syntax?
How to pass arguments to inline GCC/Clang asembly with Intel syntax?
wish help you to fix your issue As a rule of thumb, gcc inline assembly must be written in ATT syntax to compile normally. You can compile with -masm=intel to use Intel syntax, but then your code won't compile without this flag. It is possible to pro
TAG : gcc
Date : September 26 2020, 07:00 PM , By : John Ryan
How to interact with RISC-V CSRs by using GCC C code?
How to interact with RISC-V CSRs by using GCC C code?
this will help this is my first question to be asked here on stackoverflow, so please be kind with me ;) , You can use the I constraint for an immediate constant argument:
TAG : gcc
Date : September 26 2020, 11:00 AM , By : Prabhat Acharya
Why does this MakeFile rule have two colons?
Why does this MakeFile rule have two colons?
Any of those help This is a static pattern rule. See the linked GNU make documentation.
TAG : gcc
Date : September 25 2020, 09:00 PM , By : Matheus Poleza
How to use 32-bit w registers in ARM aarch64 GCC inline assembly?
How to use 32-bit w registers in ARM aarch64 GCC inline assembly?
To fix the issue you can do I can use 64-bit registers for example as in: , It can be done by adding the w in front of the %, e.g.:
TAG : gcc
Date : September 22 2020, 02:00 AM , By : Joachim Rorbol
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