DOCUMENT:Q150884 30-JUL-2001 [visualc] TITLE :FIX: C1001 Fatal Error in File Main.c, Line 413 for /O1 or /O2 PRODUCT :Microsoft C Compiler PROD/VER:4.00 4.10 OPER/SYS: KEYWORDS:kbCompiler kbCPPonly kbVC ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The C/C++ Compiler (CL.EXE), included with: - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 ------------------------------------------------------------------------------- SYMPTOMS ======== Using /O1 (minimize size) or /O2 (maximize speed) causes a C1001 error in a try block with the following error message: fatal error C1001: INTERNAL COMPILER ERROR (compiler file '\school.tp3\test\c10\src\P2\main.c', line 413) Additionally, C++ exception handling must be enabled (/GX). If the warning level is set to 4 (/W4), C4702 (unreachable code) warnings are issued before the C1001 fatal error. CAUSE ===== The cause of the problem is having both /Og (global optimizations) and inline function expansion /Ob1 (Only __inline) or /Ob2 (Any Suitable) compiling. /O1 and /O2 are both compound switches, including /Og and /Ob1. RESOLUTION ========== Disable either global optimizations (/Og-) or inline function expansion (/Ob1- or /Ob2-). Please see the More Information section below. STATUS ====== Microsoft has confirmed this to be bug in the Microsoft products listed at the beginning of this article. This bug was corrected in Visual C++ 32-bit Edition version 4.2. MORE INFORMATION ================ The following code reproduces the error when compiled: // Compile option needed are: /GX, /W4, and /O1(minimize size) // or /O2 (maximize speed) struct A { ~A(){} }; struct B { A a; }; void main(void) { try // line 17 { B *pB = new B[4]; delete [] pB; // line 20, warning C4702: unreachable code } catch(...) { } } The following error message is generated: test.cpp(17) : fatal error C1001: INTERNAL COMPILER ERROR (compiler file '\school.tp3\test\c10\src\P2\main.c', line 413) Compiling from command line with both /Og (global optimizations) and in-line function expansion, /Ob1(Only __inline) or /Ob2 (Any Suitable), reproduces the error. For instance, using: cl /Og /Ob1 /GX /W4 test.cpp Compiling with the following switch settings in command line does not produce errors: cl /Og /GX /W4 test.cpp - or - cl /Ob1 /GX /W4 test.cpp One workaround when using /O1 or /O2 in Developer Studio is to disable In-line function expansion (Build:Settings, C++ Tab, Optimizations category). Another workaround is to disable global optimizations. To accomplish this, choose Custom for the type of optimization (Build:Settings, C++ Tab, Optimizations category). Check all categories that apply, but do not check global optimizations. This behavior is similar to using the components of /O1 or /O2 and eliminating /Og). An additional method is to leave /O1 or /O2 intact and manually add /Og- to the Project Options. Additional query words: kbVC400bug 4.00 4.10 4.20 vcfixlist420 CPPIss ====================================================================== Keywords : kbCompiler kbCPPonly kbVC Technology : kbVCsearch kbAudDeveloper kbCVCComp Version : 4.00 4.10 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.