# 生成有详细信息的汇编文件 ## 例子 #include <stdio.h> int main(void) { int i; for (i = 0; i < 10; i++) printf("%d ", i); putchar ('\n'); return 0; } ## 技巧 使用`-fverbose-asm`选项就可以生成带有详细信息的汇编文件： $ gcc -S -fverbose-asm foo.c $ cat foo.s .file "foo.c" # GNU C (Ubuntu/Linaro 4.6.3-1ubuntu5) version 4.6.3 (x86_64-linux-gnu) # compiled by GNU C version 4.6.3, GMP version 5.0.2, MPFR version 3.1.0-p3, MPC version 0.9 # GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 # options passed: -imultilib . -imultiarch x86_64-linux-gnu foo.c # -mtune=generic -march=x86-64 -fverbose-asm -fstack-protector # options enabled: -fasynchronous-unwind-tables -fauto-inc-dec # -fbranch-count-reg -fcommon -fdelete-null-pointer-checks -fdwarf2-cfi-asm # -fearly-inlining -feliminate-unused-debug-types -ffunction-cse -fgcse-lm # -fident -finline-functions-called-once -fira-share-save-slots # -fira-share-spill-slots -fivopts -fkeep-static-consts # -fleading-underscore -fmath-errno -fmerge-debug-strings # -fmove-loop-invariants -fpeephole -fprefetch-loop-arrays # -freg-struct-return -fsched-critical-path-heuristic # -fsched-dep-count-heuristic -fsched-group-heuristic -fsched-interblock # -fsched-last-insn-heuristic -fsched-rank-heuristic -fsched-spec # -fsched-spec-insn-heuristic -fsched-stalled-insns-dep -fshow-column # -fsigned-zeros -fsplit-ivs-in-unroller -fstack-protector # -fstrict-volatile-bitfields -ftrapping-math -ftree-cselim -ftree-forwprop # -ftree-loop-if-convert -ftree-loop-im -ftree-loop-ivcanon # -ftree-loop-optimize -ftree-parallelize-loops= -ftree-phiprop -ftree-pta # -ftree-reassoc -ftree-scev-cprop -ftree-slp-vectorize # -ftree-vect-loop-version -funit-at-a-time -funwind-tables # -fvect-cost-model -fverbose-asm -fzero-initialized-in-bss # -m128bit-long-double -m64 -m80387 -maccumulate-outgoing-args # -malign-stringops -mfancy-math-387 -mfp-ret-in-387 -mglibc -mieee-fp # -mmmx -mno-sse4 -mpush-args -mred-zone -msse -msse2 -mtls-direct-seg-refs # Compiler executable checksum: 75e879ed14f91af504f4150eadeaa0e6 .section .rodata .LC0: .string "%d " .text .globl main .type main, @function main: .LFB0: .cfi_startproc pushq %rbp # .cfi_def_cfa_offset 16 .cfi_offset 6, -16 movq %rsp, %rbp #, .cfi_def_cfa_register 6 subq $16, %rsp #, movl $0, -4(%rbp) #, i jmp .L2 # .L3: movl $.LC0, %eax #, D.2049 movl -4(%rbp), %edx # i, tmp62 movl %edx, %esi # tmp62, movq %rax, %rdi # D.2049, movl $0, %eax #, call printf # addl $1, -4(%rbp) #, i .L2: cmpl $9, -4(%rbp) #, i jle .L3 #, movl $10, %edi #, call putchar # movl $0, %eax #, D.2050 leave .cfi_def_cfa 7, 8 ret .cfi_endproc .LFE0: .size main, .-main .ident "GCC: (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3" .section .note.GNU-stack,"",@progbits 可以看到，在汇编文件中给出了gcc所使用的具体选项，以及汇编指令操作数所对应的源程序（或中间代码）中的变量。 详情参见[gcc手册](https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#index-fverbose-asm-2614) ## 贡献者 xmj