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T32 C libraries

The linker automatically links in the T32 C library if it detects that one or more of the objects to be linked have been built for T32 code using the armclang command-line option -mthumb.

Despite its name, the T32 C library might not contain exclusively T32 code. If A32 instructions are available, the T32 library might use them to improve the performance of critical functions such as memcpy(), memset(), and memclr(). The bulk of the T32 C library, however, is coded in T32 instructions for the best code density.

For an A32 instruction-only build, compile with the --arm_only option.