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Bug 509

Summary: g++ 4.7.1 warning (enumeral and non-enumeral type in conditional expression)
Product: Eigen Reporter: Benjamin Piwowarski <benjamin>
Component: Core - generalAssignee: Nobody <eigen.nobody>
Severity: Unknown CC: gael.guennebaud, jacob.benoit.1
Priority: Normal    
Version: 3.1   
Hardware: All   
OS: All   
Description Flags
Sample C++ code producing the warning none

Description Benjamin Piwowarski 2012-09-05 16:37:08 UTC
Created attachment 294 [details]
Sample C++ code producing the warning

Compiling the attachment with -Wextra results in a warning with g++ 4.7.1 (with g++ 4.2.1 there is no warning)

$ g++-4.7 -Wextra  -o a

In file included from Eigen/Core:246:0,
                 from Eigen/SparseCore:4,
                 from Eigen/Sparse:17,
Eigen/src/Core/util/XprHelper.h: In instantiation of 'struct Eigen::internal::nested<Eigen::SparseSparseProduct<const Eigen::SparseMatrix<double>&, const Eigen::SparseMatrix<double>&>, 1, Eigen::SparseMatrix<double, 6, int> >':
Eigen/src/SparseCore/SparseProduct.h:85:5:   required from 'class Eigen::SparseSparseProduct<const Eigen::SparseMatrix<double>&, const Eigen::SparseMatrix<double>&>'   required from here
Eigen/src/Core/util/XprHelper.h:296:8: warning: enumeral and non-enumeral type in conditional expression [enabled by default]
Comment 1 Benjamin Piwowarski 2012-09-05 16:49:01 UTC
A quick fix is to modify ScalarReadCostAsInteger and CoeffReadCostAsInteger:

in XprHelper.h (line 304)
    ScalarReadCostAsInteger = ScalarReadCost == Dynamic ? int(DynamicAsInteger) : int(ScalarReadCost),
    CoeffReadCostAsInteger = CoeffReadCost == Dynamic ? int(DynamicAsInteger) : int(CoeffReadCost),
Comment 2 Gael Guennebaud 2012-09-26 23:36:11 UTC
thanks for the report,
changeset:   c7a5c5a5658d
user:        ggael
date:        2012-09-26 23:32:22
summary:     fix bug 509: warning with gcc 4.7
changeset:   8fe4e0bd2fa5
branch:      3.1
user:        ggael
date:        2012-09-26 23:32:22
summary:     fix bug 509: warning with gcc 4.7
(transplanted from c7a5c5a5658d8b83b7d764b359e908fbc70a985b)
Comment 3 Nobody 2019-12-04 11:52:46 UTC
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