NekoCWD/libcamera
NekoCWD/libcamera
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages 7 Wiki Activity Actions

libcamera: matrix: Fix compilation error in inverse() function

Browse source 
Some gcc versions report uninitialized variable usage:

In member function ‘constexpr T& libcamera::Span<T, 4294967295>::operator[](size_type) const [with T = unsigned int]’,
    inlined from ‘void libcamera::matrixInvert(Span<const T>, Span<T, 4294967295>, unsigned int, Span<T, 4294967295>, Span<unsigned int>)::MatrixAccessor::swap(unsigned int, unsigned int) [with T = float]’ at ../../src/libcamera/matrix.cpp:194:13,
    inlined from ‘bool libcamera::matrixInvert(Span<const T>, Span<T, 4294967295>, unsigned int, Span<T, 4294967295>, Span<unsigned int>) [with T = float]’ at ../../src/libcamera/matrix.cpp:255:14:
../../include/libcamera/base/span.h:362:76: error: ‘row’ may be used uninitialized [-Werror=maybe-uninitialized]
  362 |         constexpr reference operator[](size_type idx) const { return data()[idx]; }
      |                                                                      ~~~~~~^
../../src/libcamera/matrix.cpp: In function ‘bool libcamera::matrixInvert(Span<const T>, Span<T, 4294967295>, unsigned int, Span<T, 4294967295>, Span<unsigned int>) [with T = float]’:
../../src/libcamera/matrix.cpp:232:30: note: ‘row’ was declared here
  232 |                 unsigned int row;
      |                              ^~~

This is a false positive. Fix it by initializing the variable when
declaring it.

Fixes: 6287ceff5a ("libcamera: matrix: Add inverse() function")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Tested-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Tested-by: Milan Zamazal <mzamazal@redhat.com>
This commit is contained in:
Laurent Pinchart 2025-05-22 14:38:00 +02:00
parent d997e97512
commit 516f365670
1 changed files with 1 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

2
src/libcamera/matrix.cpp
View file

@ -229,7 +229,7 @@ bool matrixInvert(Span<const T> dataIn, Span<T> dataOut, unsigned int dim,
* Locate the next pivot. To improve numerical stability, use * Locate the next pivot. To improve numerical stability, use
* the row with the largest value in the pivot's column. * the row with the largest value in the pivot's column.
*/ */
unsigned int row; unsigned int row = pivot;
T maxValue{ 0 }; T maxValue{ 0 };
for (unsigned int i = pivot; i < dim; ++i) { for (unsigned int i = pivot; i < dim; ++i) {