gcc - Is this a valid C program? -


i wrote program, size of array taken input user.

#include <stdio.h> main() {     int x;     scanf("%d", &x);     int y[x];     /* stuff */ }

this program failed compile on school's compiler turbo c (an antique compiler). when tried on pc gnu cc, compiled successfully.

so question is, valid c program? can set size of array using user's input?

c90 not support variable length arrays can see using command line:

gcc -std=c90 -pedantic code.c

you see error message this:

warning: iso c90 forbids variable length array ‘y’ [-wvla]

but c99 valid:

gcc -std=c99 -pedantic code.c

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