https://gcc.gnu.org/g:79b49977b1894a0a5eea3d2125eb6546b9d0cf02
commit r16-4562-g79b49977b1894a0a5eea3d2125eb6546b9d0cf02 Author: Jakub Jelinek <[email protected]> Date: Wed Oct 22 13:11:52 2025 +0200 c++: Fix up RAW_DATA_CST handling in braced_list_to_string [PR122302] The following testcase is miscompiled, because a RAW_DATA_CST tree node is shared by multiple CONSTRUCTORs and when the braced_list_to_string function changes one to extend the RAW_DATA_CST over the single preceding and single succeeding INTEGER_CST, it changes the RAW_DATA_CST in the other CONSTRUCTOR where the elts around it are still present. Fixed by tweaking a copy of it instead, like we handle it in other spots. 2025-10-22 Jakub Jelinek <[email protected]> PR c++/122302 * c-common.cc (braced_list_to_string): Call copy_node on RAW_DATA_CST before changing RAW_DATA_POINTER and RAW_DATA_LENGTH on it. * g++.dg/cpp0x/pr122302.C: New test. * g++.dg/cpp/embed-27.C: New test. Diff: --- gcc/c-family/c-common.cc | 1 + gcc/testsuite/g++.dg/cpp/embed-27.C | 38 +++++++++++++++++++++++++++++++++ gcc/testsuite/g++.dg/cpp0x/pr122302.C | 40 +++++++++++++++++++++++++++++++++++ 3 files changed, 79 insertions(+) diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc index 54e16f708134..f2eed0337065 100644 --- a/gcc/c-family/c-common.cc +++ b/gcc/c-family/c-common.cc @@ -10296,6 +10296,7 @@ braced_list_to_string (tree type, tree ctor, bool member) j = i - start; else j -= start; + value = copy_node (value); RAW_DATA_POINTER (value) -= start; RAW_DATA_LENGTH (value) += start + end; i += end; diff --git a/gcc/testsuite/g++.dg/cpp/embed-27.C b/gcc/testsuite/g++.dg/cpp/embed-27.C new file mode 100644 index 000000000000..dffb8b981a19 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp/embed-27.C @@ -0,0 +1,38 @@ +// PR c++/122302 +// { dg-do run { target c++11 } } +// { dg-options "-O2" } + +unsigned char b[] = { +#embed "embed-27.C" +}; + +struct A { + unsigned char a[sizeof (b)] = { +#embed "embed-27.C" + }; +}; + +void +foo () +{ + A a; + for (int i = 0; i < sizeof (b); ++i) + if (a.a[i] != b[i]) + __builtin_abort (); +} + +void +bar () +{ + A a; + for (int i = 0; i < sizeof (b); ++i) + if (a.a[i] != b[i]) + __builtin_abort (); +} + +int +main () +{ + foo (); + bar (); +} diff --git a/gcc/testsuite/g++.dg/cpp0x/pr122302.C b/gcc/testsuite/g++.dg/cpp0x/pr122302.C new file mode 100644 index 000000000000..248b6a4f7898 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/pr122302.C @@ -0,0 +1,40 @@ +// PR c++/122302 +// { dg-do run { target c++11 } } +// { dg-options "-O2" } + +struct A { + unsigned char a[130] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 1, 2 }; +}; + +void +foo () +{ + A a; + for (int i = 0; i < 130; ++i) + if (a.a[i] != (i & 15) + 1) + __builtin_abort (); +} + +void +bar () +{ + A a; + for (int i = 0; i < 130; ++i) + if (a.a[i] != (i & 15) + 1) + __builtin_abort (); +} + +int +main () +{ + foo (); + bar (); +}
