There was a cut&pasto in the rr_and_mask's adjustment to match the combined type: the test on whether there was a mask already was testing the wrong variable, and then it might crash or otherwise fail accessing an undefined mask. This only hit with checking enabled, and rarely at that.
Regstrapped on x86_64-linux-gnu. Ok to install? for gcc/ChangeLog PR tree-optimization/118344 * gimple-fold.cc (fold_truth_andor_for_ifcombine): Fix typo in rr_and_mask's type adjustment test. for gcc/testsuite/ChangeLog PR tree-optimization/118344 * gcc.dg/field-merge-19.c: New. --- gcc/gimple-fold.cc | 2 +- gcc/testsuite/gcc.dg/field-merge-19.c | 41 +++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/field-merge-19.c diff --git a/gcc/gimple-fold.cc b/gcc/gimple-fold.cc index 0ad92de3a218f..20b5024d861db 100644 --- a/gcc/gimple-fold.cc +++ b/gcc/gimple-fold.cc @@ -8644,7 +8644,7 @@ fold_truth_andor_for_ifcombine (enum tree_code code, tree truth_type, xlr_bitpos); else lr_mask = wi::shifted_mask (xlr_bitpos, lr_bitsize, false, rnprec); - if (rl_and_mask.get_precision ()) + if (rr_and_mask.get_precision ()) rr_mask = wi::lshift (wide_int::from (rr_and_mask, rnprec, UNSIGNED), xrr_bitpos); else diff --git a/gcc/testsuite/gcc.dg/field-merge-19.c b/gcc/testsuite/gcc.dg/field-merge-19.c new file mode 100644 index 0000000000000..5622baa52b0a3 --- /dev/null +++ b/gcc/testsuite/gcc.dg/field-merge-19.c @@ -0,0 +1,41 @@ +/* { dg-do compile } */ +/* { dg-options "-O3 -fchecking" } */ + +/* PR tree-optimization/118344 */ + +/* This used to ICE attempting to extend a mask variable after testing the + wrong mask variable. */ + +int d, e, g, h, i, c, j; +static short k; +char o; +static int *p; +static long *a; +int b[0]; +int q(int s, int t, int *u, int *v) { + for (int f = 0; f < s; f++) + if ((t & v[f]) != u[f]) + return 0; + return 1; +} +int w(int s, int t) { + int l[] = {t, t, t, t}, m[] = {e, e, 3, 1}; + int n = q(s, d, l, m); + return n; +} +int x(unsigned s) { + unsigned r; + if (s >= -1) + return 1; + r = 10000000; + while (s > 1 / r) + r /= 2; + return g ? 2 : 0; +} +void y() { + for (;;) { + b[w(8, *p)] = h; + for (; a + k; j = o) + i &= c = x(6) < 0; + } +} -- Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/ Free Software Activist GNU Toolchain Engineer More tolerance and less prejudice are key for inclusion and diversity Excluding neuro-others for not behaving ""normal"" is *not* inclusive