I am developing a test generator for in house compilers and have come across a difference where gcc does not agree with our compilers or the Microsoft compiler.
The result t1_2a of the expression is what differs between gcc and other compilers. This is on gcc (GCC) 3.4.6 20060404 (Red Hat 3.4.6-9), and does not matter what the platform is. Compiled with: $ gcc4 test.c -o test.exe $ ./test.exe Error: t1_2a ffffffff t1_2b 22a8b02e t1_2c 0 Working: t2_2a 0 t2_2b 0 When compared to running on Visual Studio: $ cl test.c Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 14.00.50727.762 for 80x86 Copyright (C) Microsoft Corporation. All rights reserved. test.c Microsoft (R) Incremental Linker Version 8.00.50727.762 Copyright (C) Microsoft Corporation. All rights reserved. /out:test.exe test.obj $ ./test.exe Error: t1_2a 0 t1_2b 22a8b02e t1_2c 0 Working: t2_2a 0 t2_2b 0 -- Summary: Expressions result is wrong Product: gcc Version: 4.1.2 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: peter at xmos dot com GCC build triplet: gcc version 4.1.2 20070626 (Red Hat 4.1.2-14) GCC host triplet: Linux 2.6.9-67.ELsmp #1 SMP Wed Nov 7 13:56:44 EST 2007 x86_64 x GCC target triplet: Target: x86_64-redhat-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36077