waf - build works, custom build targets fail - c

Question

The waf command waf build shows compiler errors (if there are any) while waf debug or waf release does not and always fails, utilizing the following wscript file (or maybe the wscript file has some other shortcomings I am currently not aware of):
APPNAME = 'waftest'
VERSION = '0.0.1'
def configure(ctx):
ctx.load('compiler_c')
ctx.define('VERSION', VERSION)
ctx.define('GETTEXT_PACKAGE', APPNAME)
ctx.check_cfg(atleast_pkgconfig_version='0.1.1')
ctx.check_cfg(package='glib-2.0', uselib_store='GLIB', args=['--cflags', '--libs'], mandatory=True)
ctx.check_cfg(package='gobject-2.0', uselib_store='GOBJECT', args=['--cflags', '--libs'], mandatory=True)
ctx.check_cfg(package='gtk+-3.0', uselib_store='GTK3', args=['--cflags', '--libs'], mandatory=True)
ctx.check_cfg(package='libxml-2.0', uselib_store='XML', args=['--cflags', '--libs'], mandatory=True)
ctx.check_large_file(mandatory=False)
ctx.check_endianness(mandatory=False)
ctx.check_inline(mandatory=False)
ctx.setenv('debug')
ctx.env.CFLAGS = ['-g', '-Wall']
ctx.define('DEBUG',1)
ctx.setenv('release')
ctx.env.CFLAGS = ['-O2', '-Wall']
ctx.define('RELEASE',1)
def pre(ctx):
print ('Building [[[' + ctx.variant + ']]] ...')
def post(ctx):
print ('Building is complete.')
def build(ctx):
ctx.add_pre_fun(pre)
ctx.add_post_fun(post)
# if not ctx.variant:
# ctx.fatal('Do "waf debug" or "waf release"')
exe = ctx.program(
features = ['c', 'cprogram'],
target = APPNAME+'.bin',
source = ctx.path.ant_glob(['src/*.c']),
includes = ['src/'],
export_includes = ['src/'],
uselib = 'GOBJECT GLIB GTK3 XML'
)
# for item in exe.includes:
# print(item)
from waflib.Build import BuildContext
class release(BuildContext):
cmd = 'release'
variant = 'release'
class debug(BuildContext):
cmd = 'debug'
variant = 'debug'
Error resulting from waf debug :
Build failed
-> task in 'waftest.bin' failed (exit status -1):
{task 46697488: c qqq.c -> qqq.c.1.o}
[useless filepaths]
I had a look at the waf demos, read the wafbook at section 6.2.2 but those did not supply me with valuable information in order to fix this issue.
What's wrong, and how do I fix it?

Answer 1

You need to do at least the following:
def configure(ctx):
...
ctx.setenv('debug')
ctx.load('compiler_c')
...
Since the cfg.setenv function resets whole previous environment. If you want to save previous environment, you can do cfg.setenv('debug', env=cfg.env.derive()).
Also, you don't need to explicitly specify the features = ['c', 'cprogram'], since, it's redundant, when you call bld.program(...).
P.S. Don't forget to reconfigure after modifying wscript file.