On 22.12.2016 19:20, Richard Sandiford wrote:
Georg-Johann Lay <a...@gjlay.de> writes:
One test case used unsigned long for the 3rd parameter of memset, which
should be size_t. This made the test crash for targets where correct
parameter passing depends on correct prototypes.
Fixed and committed as obvious.
Catching up on backlog, but... I'm not sure this counts as obvious
if the crash was an ICE. We should at least fail gracefully.
The crash I mentioned happened on avr where parameter passing needs
correct prototypes. The code crashed when executed on avr because
a long gets passed in regs R22..R25 (LSBs first) but a size_t is
passed in R24..R25. Hence the implementation of memset would pick
up the upper two bytes of the length (zero) which crashes when run.
PR30778 was about wrong-code because more than the specified number
of bytes were written. It was reported for x64_64 where we have
size_t = unsigned long, hence the change is a no-op on the platform
the PR was originally reported against (similar for x86 where
size_t = unsigned).
Moreover, the test case is condensed from GCC's combine.c and I'd
expect that GCC's header are using correct prototypes :-)
Johann
Thanks,
Richard
Johann
gcc/testsuite/
* gcc.c-torture/execute/pr30778.c (memset): Use size_t for 3rd
parameter in declaration.
Index: gcc.c-torture/execute/pr30778.c
===================================================================
--- gcc.c-torture/execute/pr30778.c (revision 242541)
+++ gcc.c-torture/execute/pr30778.c (working copy)
@@ -1,4 +1,4 @@
-extern void *memset (void *, int, unsigned long);
+extern void *memset (void *, int, __SIZE_TYPE__);
extern void abort (void);
struct reg_stat {
