https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103955
Bug ID: 103955
Summary: std::to_chars(char*, char*, double, std::chars_format,
int precision) crashes for the two maximal int values
Product: gcc
Version: 11.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: gcc at maxmitti dot tk
Target Milestone: ---
Created attachment 52148
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52148&action=edit
preprocessed source
Calling std::to_chars(char*, char*, double, std::chars_format, int precision)
with a precision of 2147483647 or 2147483646 and a small buffer causes a
segmentation fault.
2147483645 and smaller return an error correctly.
The preprocessed source was created with GCC 11.1.0, but the crash also happens
with compiler-explorer’s 11.2 and trunk build and even with clang 13 when using
libstdc++, but not with libc++.
Example on compiler explorer: https://godbolt.org/z/c63qbWff4
gcc output follows:
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/lto-wrapper
Target: x86_64-pc-linux-gnu
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gdc_include_dir=/usr/include/dlang/gdc
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 11.1.0 (GCC)
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ignoring nonexistent directory
"/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/../../../../x86_64-pc-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/../../../../include/c++/11.1.0
/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/../../../../include/c++/11.1.0/x86_64-pc-linux-gnu
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GNU C++20 (GCC) version 11.1.0 (x86_64-pc-linux-gnu)
compiled by GNU C version 11.1.0, GMP version 6.2.1, MPFR version
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GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU C++20 (GCC) version 11.1.0 (x86_64-pc-linux-gnu)
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COMPILER_PATH=/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/:/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/:/usr/lib/gcc/x86_64-pc-linux-gnu/:/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/:/usr/lib/gcc/x86_64-pc-linux-gnu/
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