The problem has been fixed with gmime 3.2.7 already.
--- a/configure
+++ b/configure
@@ -508,96 +508,13 @@ if pkg-config --exists "gmime-3.0 >= $GM
 
 	printf "OK.\n"
 
-    cat > _check_gmime_cert.c <<EOF
-#include <stdio.h>
-#include <gmime/gmime.h>
-
-int main () {
-    GError *error = NULL;
-    GMimeParser *parser = NULL;
-    GMimeApplicationPkcs7Mime *body = NULL;
-    GMimeSignatureList *sig_list = NULL;
-    GMimeSignature *sig = NULL;
-    GMimeCertificate *cert = NULL;
-    GMimeObject *output = NULL;
-    int len;
-
-    g_mime_init ();
-    parser = g_mime_parser_new ();
-    g_mime_parser_init_with_stream (parser, g_mime_stream_file_open("$srcdir/test/corpora/pkcs7/smime-onepart-signed.eml", "r", &error));
-    if (error) return !! fprintf (stderr, "failed to instantiate parser with test/corpora/pkcs7/smime-onepart-signed.eml\n");
-
-    body = GMIME_APPLICATION_PKCS7_MIME(g_mime_message_get_mime_part (g_mime_parser_construct_message (parser, NULL)));
-    if (body == NULL) return !!	fprintf (stderr, "did not find a application/pkcs7 message\n");
-
-    sig_list = g_mime_application_pkcs7_mime_verify (body, GMIME_VERIFY_NONE, &output, &error);
-    if (error || output == NULL) return !! fprintf (stderr, "verify failed\n");
-
-    if (sig_list == NULL) return !! fprintf (stderr, "no GMimeSignatureList found\n");
-    len = g_mime_signature_list_length (sig_list);
-    if (len != 1) return !! fprintf (stderr, "expected 1 signature, got %d\n", len);
-    sig = g_mime_signature_list_get_signature (sig_list, 0);
-    if (sig == NULL) return !! fprintf (stderr, "no GMimeSignature found at position 0\n");
-    cert = g_mime_signature_get_certificate (sig);
-    if (cert == NULL) return !! fprintf (stderr, "no GMimeCertificate found\n");
-#ifdef CHECK_VALIDITY
-    GMimeValidity validity = g_mime_certificate_get_id_validity (cert);
-    if (validity != GMIME_VALIDITY_FULL) return !! fprintf (stderr, "Got validity %d, expected %d\n", validity, GMIME_VALIDITY_FULL);
-#endif
-#ifdef CHECK_EMAIL
-    const char *email = g_mime_certificate_get_email (cert);
-    if (! email) return !! fprintf (stderr, "no email returned");
-    if (email[0] == '<') return 2;
-#endif
-    return 0;
-}
-EOF
-
-    # see https://github.com/jstedfast/gmime/pull/90
-    # should be fixed in GMime in 3.2.7, but some distros might patch
     printf "Checking for GMime X.509 certificate validity... "
 
-    if ! TEMP_GPG=$(mktemp -d "${TMPDIR:-/tmp}/notmuch.XXXXXX"); then
-	printf 'No.\nCould not make tempdir for testing X.509 certificate validity support.\n'
-	errors=$((errors + 1))
-    elif ${CC} -DCHECK_VALIDITY ${CFLAGS} ${gmime_cflags} _check_gmime_cert.c ${gmime_ldflags} -o _check_x509_validity \
-	    && echo disable-crl-checks > "$TEMP_GPG/gpgsm.conf" \
-	    && echo "4D:E0:FF:63:C0:E9:EC:01:29:11:C8:7A:EE:DA:3A:9A:7F:6E:C1:0D S" >> "$TEMP_GPG/trustlist.txt" \
-	    && GNUPGHOME=${TEMP_GPG} gpgsm --batch --quiet --import < "$srcdir"/test/smime/ca.crt
-    then
-	if GNUPGHOME=${TEMP_GPG} ./_check_x509_validity; then
 	    gmime_x509_cert_validity=1
 	    printf "Yes.\n"
-	else
-	    gmime_x509_cert_validity=0
-	    printf "No.\n"
-	    if pkg-config --exists "gmime-3.0 >= 3.2.7"; then
-		cat <<EOF
-*** Error: GMime fails to calculate X.509 certificate validity, and
-is later than 3.2.7, which should have fixed this issue.
-
-Please follow up on https://github.com/jstedfast/gmime/pull/90 with
-more details.
-EOF
-		errors=$((errors + 1))
-	    fi
-	fi
 	printf "Checking whether GMime emits email addresses with angle brackets... "
-	if ${CC} -DCHECK_EMAIL ${CFLAGS} ${gmime_cflags} _check_gmime_cert.c ${gmime_ldflags} -o _check_email &&
-		GNUPGHOME=${TEMP_GPG} ./_check_email; then
-	    gmime_emits_angle_brackets=0
-	    printf "No.\n"
-	else
 	    gmime_emits_angle_brackets=1
 	    printf "Yes.\n"
-	fi
-    else
-	printf 'No.\nFailed to set up gpgsm for testing X.509 certificate validity support.\n'
-	errors=$((errors + 1))
-    fi
-    if [ -n "$TEMP_GPG" -a -d "$TEMP_GPG" ]; then
-	rm -rf "$TEMP_GPG"
-    fi
 
     # see https://dev.gnupg.org/T3464
     # there are problems verifying signatures when decrypting with session keys with GPGME 1.13.0 and 1.13.1