Catch2: SECTION execution regression

Given this test:

TEST_CASE("catch/siblingSections", "")
{
    printf("0");
    SECTION("s1", "") {
        printf("1");
    }
    SECTION("s2", "") {
        printf("2");
    }
    SECTION("s3", "") {
        printf("3");
    }
    printf("\n");
}

Pre-1.0 the output used to be:

01 02 03

With current tip the test prints instead:

0 01 02 03

More curiously, given this test:

TEST_CASE("catch/nestedSections", "")
{
    printf("0");
    SECTION("s1", "") {
        printf("1");
        SECTION("s2", "") {
            printf("2");
            SECTION("s3", "") {
                printf("3");
            }
        }
    }
    printf("\n");
}

Pre-1.0 the output used to be:

0123

While with current tip the test prints:

0 01 012 0123