使用gdb进行调试时找不到调试符号

Question

我正在使用gdb调试C4.5代码，但出现错误

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Reading symbols from ./consult...(no debugging symbols found)...done.

C4.5的make文件在CFLAG中具有-g，并且附加了整个文件。 我遵循了一些讨论以进行类似的讨论。 但是还是有问题的。

Makefile
CFLAGS = -g -O2    
core.ln = \
    getnames.ln getdata.ln trees.ln getopt.ln header.ln    
trees.ln = \
    besttree.ln build.ln info.ln discr.ln contin.ln subset.ln\
    prune.ln stats.ln st-thresh.ln classify.ln confmat.ln\
    sort.ln $(core.ln)    
rules.ln = \
    rules.ln genlogs.ln genrules.ln makerules.ln prunerule.ln\
    siftrules.ln testrules.ln stats.ln confmat.ln sort.ln $(core.ln)    
core = \
    getnames.o getdata.o trees.o getopt.o header.o    
trees = \
    besttree.o build.o info.o discr.o contin.o subset.o prune.o\
    stats.o st-thresh.o classify.o confmat.o sort.o $(core)    
rules = \
    rules.o genlogs.o genrules.o makerules.o prunerule.o\
    siftrules.o testrules.o stats.o confmat.o sort.o $(core)    
c4.5:   c4.5.o $(trees)
cc -o c4.5 c4.5.o $(trees) -lm   
c4.5gt:
    cat defns.i types.i\
        c4.5.c\
        besttree.c build.c info.c discr.c contin.c subset.c\
        prune.c stats.c st-thresh.c confmat.c sort.c\
        getnames.c getdata.c classify.c trees.c header.c\
        | egrep -v 'defns.i|types.i|extern.i|buildex.i' >c4.5gt.c
    cc -O4 -o c4.5gt c4.5gt.c -lm
    rm c4.5gt.c  
c4.5rules: c4.5rules.o $(rules)
    cc -o c4.5rules c4.5rules.o $(rules) -lm  

c4.5rulesgt:
    cat defns.i types.i\
        c4.5rules.c\
        rules.c genlogs.c genrules.c makerules.c prunerule.c\
        siftrules.c testrules.c stats.c confmat.c sort.c\
        getnames.c getdata.c classify.c trees.c header.c\
        | egrep -v 'defns.i|types.i|extern.i|rulex.i' >c4.5rulesgt.c
    cc -O4 -o c4.5rulesgt c4.5rulesgt.c -lm
    rm c4.5rulesgt.c    
consult: consult.o userint.o $(core)
    cc -o consult consult.o userint.o $(core)    
consultr: consultr.o rules.o userint.o $(core)

    cc -o consultr consultr.o rules.o userint.o $(core)


.c.o:
    cc $(CFLAGS) -c $<


all:
    make c4.5
    make c4.5rules
    make consult
    make consultr
    cc -o xval-prep xval-prep.c
    cc -o average average.c -lm


$(trees): defns.i types.i extern.i
$(rules): defns.i types.i extern.i

当我检查文件咨询是否已剥离/未剥离时，它不会被剥离。 我还需要添加什么到make文件中，以便可以使用gdb调试Consult api？ 谢谢

Answer 1

这有效

cc -ggdb3 -O0 -std=c11  -Wshadow ab.c -o ab


taras@taras: $ gdb ./ab

GNU gdb (Ubuntu 7.11.1-0ubuntu1~16.04) 7.11.1
...

Reading symbols from ./ab...done.

Starting program: /home/taras/ab 7

(gdb) b 7

Breakpoint 1 at 0x40052e: file ab.c, line 7.

(gdb) r

Starting program: /home/taras/ab 7

Breakpoint 1, main () at ab.c:7

7               int n = 0, m = 0;

(gdb) n