invalid variable name errors in cygwin

[Rüdiger Ranft]

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Hi list,

when I try to run my configure it complains about invalid variable names
given to the script[1]. I tried to get the source of the problem, it
seems the lines

~  *=*)
~    ac_envvar=`expr "x$ac_option" : 'x\([^=]*\)='`
~    # Reject names that are not valid shell variable names.
~    expr "x$ac_envvar" : ".*[^_$as_cr_alnum]" >/dev/null &&
~      { echo "$as_me: error: invalid variable name: $ac_envvar" >&2
~   { (exit 1); exit 1; }; }

are causing the problem. To debug the script I added an
        echo "checking expression '$ac_option'"
under the
        *=*)
line to see the expression which the script tries to check. But after
adding this line the problem disapeared[2], so I don't know how to debug
the script. Also I don't want to edit the configure script every time
after I runned autoconf.

The configure line which caused the problems was
../configure -C --prefix=/usr "CXXFLAGS=-Wall -Werror" "CFLAGS=-Wall
- -Werror"

So where can I dig to solve this issue?

TIA
Rudi

[1] messages of the unpatched configure script:
configure: error: invalid variable name: CXXFLAGS

[2] messages of the patched script:
checking expression 'CXXFLAGS=-Wall -Werror'
checking expression 'CFLAGS=-Wall -Werror'
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for gawk... gawk

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