https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97424
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by David Malcolm <dmalc...@gcc.gnu.org>: https://gcc.gnu.org/g:5e00ad3ffbfb4df7242c313a0d836f5b538eb2fb commit r11-4930-g5e00ad3ffbfb4df7242c313a0d836f5b538eb2fb Author: David Malcolm <dmalc...@redhat.com> Date: Wed Nov 11 21:16:45 2020 -0500 analyzer: warn on invalid shift counts [PR97424] This patch implements -Wanalyzer-shift-count-negative and -Wanalyzer-shift-count-overflow, analogous to the C/C++ warnings -Wshift-count-negative and -Wshift-count-overflow, but implemented via interprocedural path analysis rather than via parsing in a front end, and thus capable of detecting interprocedural cases that the warnings implemented in the front ends can miss. gcc/analyzer/ChangeLog: PR tree-optimization/97424 * analyzer.opt (Wanalyzer-shift-count-negative): New. (Wanalyzer-shift-count-overflow): New. * region-model.cc (class shift_count_negative_diagnostic): New. (class shift_count_overflow_diagnostic): New. (region_model::get_gassign_result): Complain about shift counts that are negative or are >= the operand's type's width. gcc/ChangeLog: PR tree-optimization/97424 * doc/invoke.texi (Static Analyzer Options): Add -Wno-analyzer-shift-count-negative and -Wno-analyzer-shift-count-overflow. (-Wno-analyzer-shift-count-negative): New. (-Wno-analyzer-shift-count-overflow): New. gcc/testsuite/ChangeLog: PR tree-optimization/97424 * gcc.dg/analyzer/invalid-shift-1.c: New test.