Issue
I want to activate c99 mode in gcc compiler to i read in other post in this forum that -std
should be equal to -std=c99
but i don't know how to set it to this value using command line so please help.
Solution
Compile using:
gcc -std=c99 -o outputfile sourcefile.c
gcc --help
lists some options, for a full list of options refer to the manuals. The different options for C dialect can be found the section "Options Controlling C Dialect" in any gcc
version's manual (e.g., here).
As you are using make
you can set the command line options for gcc using CFLAGS
:
# sample makefile
CC = gcc
CFLAGS = -Wall -std=c99
OUTFILE = outputfile
OBJS = source.o
SRCS = source.c
$(OUTFILE): $(OBJS)
$(CC) $(CFLAGS) -o $(OUTFILE) $(OBJS)
$(OBJS): $(SRCS)
$(CC) $(CFLAGS) -c $(SRCS)
Addendum (added late 2016): C99 is getting kind of old by now, people looking at this answer might want to explore C11 instead.
Answered By - jpw Answer Checked By - Clifford M. (WPSolving Volunteer)