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Diffstat (limited to 'tests/i/extern-c-struct/notes.md')
| -rw-r--r-- | tests/i/extern-c-struct/notes.md | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tests/i/extern-c-struct/notes.md b/tests/i/extern-c-struct/notes.md index 519e835..494c510 100644 --- a/tests/i/extern-c-struct/notes.md +++ b/tests/i/extern-c-struct/notes.md @@ -4,4 +4,4 @@ Human review: pending. Expected output was independently traced by AI, not captu Basis: compiler extension (EXTERN "C", INCLUDE_OBJ of a user object); a record whose fields are all C types has the layout of the matching C struct. -Trace: the harness compiles `lib.c` with the host C compiler. Sample matches `struct Sample {char; double; int}`, including the padding after the char. S is 'S', 1.5, 5. scale_sample(^S, 3) multiplies the value through the pointer to 4.5 and leaves tag and count alone, so the first line is `S 4.500000 5`. shared_sample returns the address of the static struct in lib.c, initialised to 'G', 0.5, 7, giving `G 0.500000 7`. P^.Count <- 9 writes through that pointer into the C object, so shared_count() returns 9. sum_counts receives P and Q as variadic arguments; pointers are passed unchanged and read back with va_arg(ap, struct Sample *). P points to the shared struct, whose count is now 9, and Q points to S, whose count is 5, so the last line is 9 + 5 = 14. +Trace: the harness compiles `lib.c` with the host C compiler. Sample matches `struct Sample {char; double; int}`, including the padding after the char. S is 'S', 1.5, 5. scale_sample(^S, 3) multiplies the value through the pointer to 4.5 and leaves tag and count alone, so the first line is `S 4.500000 5`. shared_sample returns the address of the static struct in lib.c, initialised to 'G', 0.5, 7, giving `G 0.500000 7`. P^.Count <- 9 writes through that pointer into the C object, so shared_count() returns 9. sum_counts receives P and Q as variadic arguments; pointers are passed unchanged and read back with va_arg(ap, struct Sample *). P points to the shared struct, whose count is now 9, and Q points to S, whose count is 5, so the last line is 9 + 5 = 14. N starts at 1. bump(^N) receives a PInt, an int * in C, and increments N to 2. Counter matches `struct Counter {int *}`; bump_counter(^C) increments through C.Target, which points to N, giving 3. get_shared(^R) receives a struct Sample ** and stores the address of the shared struct into R, so R^ shows tag G and the count 9 written earlier: `G 9`. |