I committed it. ran it again for fun. sigh. Looks like its also
triggering another issue now in g++.dg/warn/Wstringop-overflow-4.C
where its issuing:
b.C: In function ‘void test_strcpy_new_int16_t(size_t, const size_t*)’:
b.C:76:12: warning: ‘void* __builtin_memcpy(void*, const void*, long
unsigned int)’ writing 3 bytes into a region of size 0
[-Wstringop-overflow=]
76 | strcpy (d, s); \
| ~~~~~~~^~~~~~
b.C:90:3: note: in expansion of macro ‘T’
90 | T (S (2), new int16_t[r_imin_imax + 1]); // { dg-bogus "into
a region of size" "pr106120" { xfail { ilp32 && c++98_only } } }
previously, by VRP2 time we hadn't figured out the edge case, couldn't
recalculate _29 and iftmp.1_38 was unknown.
iftmp.1_38 = _29 * 2;
_40 = operator new [] (iftmp.1_38);
__builtin_memcpy (_40, &MEM <const char[37]> [(void
*)"0123456789abcdefghijklmnopqrstuvwxyz" + 34B], 3);
Now, by VRP2 we have figured it out...
_40 = operator new [] (0);
__builtin_memcpy (_40, &MEM <const char[37]> [(void
*)"0123456789abcdefghijklmnopqrstuvwxyz" + 34B], 3);
And that info is available earlier for the warnings, just hasn't been
explcitly exposed:
Do we want to change the cfail to always? something like:
diff --git a/gcc/testsuite/g++.dg/warn/Wstringop-overflow-4.C
b/gcc/testsuite/g++.dg/warn/Wstringop-overflow-4.C
index 35fb59e0232..faad5bed074 100644
--- a/gcc/testsuite/g++.dg/warn/Wstringop-overflow-4.C
+++ b/gcc/testsuite/g++.dg/warn/Wstringop-overflow-4.C
@@ -141,7 +141,7 @@ void test_strcpy_new_int16_t (size_t n, const size_t
vals[])
int r_imin_imax = SR (INT_MIN, INT_MAX);
T (S (1), new int16_t[r_imin_imax]);
- T (S (2), new int16_t[r_imin_imax + 1]); // { dg-bogus "into a region
of size" "pr106120" { xfail { ilp32 && c++98_only } } }
+ T (S (2), new int16_t[r_imin_imax + 1]); // { dg-bogus "into a region
of size" "pr106120" { xfail { c++98_only } } }
T (S (9), new int16_t[r_imin_imax * 2 + 1]);
int r_0_imax = SR (0, INT_MAX);
Of course, I dont know what this is doing on other arches... perhaps
wait for the fallout to be complete?
Andrew
On 3/30/23 12:05, Jakub Jelinek wrote:
On Thu, Mar 30, 2023 at 11:58:19AM -0400, Andrew MacLeod wrote:
On 3/30/23 09:41, Jakub Jelinek wrote:
On Wed, Mar 29, 2023 at 01:22:27PM -0400, Andrew MacLeod wrote:
however, as seems to be the case often, better ranges result in, I now get:
FAIL: 23_containers/vector/bool/allocator/copy.cc (test for excess errors)
Our middle-end warnings are just badly designed :(, the better value ranges
are, the more false positives they have.
commit 358d0ca44faf2e20fbacd0f74386308b5ca52cd4
Author: Andrew MacLeod <amacl...@redhat.com>
Date: Tue Mar 28 12:16:34 2023 -0400
Add recursive GORI recompuations with a depth limit.
LGTM for trunk, let's do with the regression incrementally.
Or as Richard mentioned on IRC, one possibility would be to force this
param temporarily to 1 (or whatever matches previous behavior) for the
diagnostic range queries).
You need a ChangeLog entry though...
Attached. I also removed the bogus warning in Walloc-13.c that no longer
happens
So incrementally deal with it.. what? just let it fail?
For today? Yes.
Ok for trunk.
commit debb8ce1f9b9d5a72d88d0ae90a6b4da5130ff59
Author: Andrew MacLeod <amacl...@redhat.com>
Date: Tue Mar 28 12:16:34 2023 -0400
Add recursive GORI recompuations with a depth limit.
PR tree-optimization/109154
gcc/
* gimple-range-gori.cc (gori_compute::may_recompute_p): Add depth
limit.
* gimple-range-gori.h (may_recompute_p): Add depth param.
* params.opt (ranger-recompute-depth): New param.
gcc/testsuite/
* gcc.dg/Walloca-13.c: Remove bogus warning that is now fixed.
Jakub
