Specify the alignment of data in common blocks and standard numeric sequence types .
The value indicates the maximum alignment (in bytes) for data elements within common blocks and standard numeric sequence types.
For example, -aligncommon=4 would align data elements with natural alignments of 4 bytes or more on 4-byte boundaries.
This option does not affect data with natural alignment smaller than the specified size.
Without -aligncommon, the compiler aligns elements in common blocks and numeric sequence types on (at most) 4-byte boundaries.
Specifying -aligncommon without a value defaults to 1 - all common block and numeric sequence type elements align on byte boundaries (no padding between elements).
-aligncommon=16 reverts to -aligncommon=8 on platforms that are not 64-bit enabled.
Do not use -aligncommon=1 with -xmemalign as these declarations will conflict and could cause a segmentation fault on some platforms and configurations.
Using —aligncommon=1 on SPARC platforms might result in a bus error due to misalignment, requiring an appropriate choice of the —xmemalign option be used. Depending on the application, —xmemalign=1s, —xmemalign=4i, or —xmemalign=8i should give optimal performance while avoiding the segmentation fault.
See also —xmemalign