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Preface Overview of the Compiler Getting Started with the Compiler Compiler Features Compiler intrinsics Performance benefits of compiler intrinsics ARM assembler instruction intrinsics Generic intrinsics Compiler intrinsics for controlling IRQ and FIQ in Compiler intrinsics for inserting optimization bar Compiler intrinsics for inserting native instructi Compiler intrinsics for Digital Signal Processing Compiler support for European Telecommunications S Overflow and carry status flags for C and C++ code Texas Instruments (TI) C55x intrinsics for optimiz Compiler support for accessing registers using nam Pragmas recognized by the compiler Compiler and processor support for bit-banding Compiler type attribute, __attribute__((bitband)) --bitband compiler command-line option How the compiler handles bit-band objects placed o Compiler support for thread-local storage Compiler support for literal pools Compiler eight-byte alignment features Precompiled Header (PCH) files Automatic Precompiled Header (PCH) file processing Precompiled Header (PCH) file processing and the h Precompiled Header (PCH) file creation requirement Compilation with multiple Precompiled Header (PCH) Obsolete Precompiled Header (PCH) files Manually specifying the filename and location of a Selectively applying Precompiled Header (PCH) file Suppressing Precompiled Header (PCH) file processi Message output during Precompiled Header (PCH) pro Performance issues with Precompiled Header (PCH) f Default compiler options that are affected by opti Compiler Coding Practices Compiler Diagnostic Messages Using the Inline and Embedded Assemblers of the AR Compiler Command-line Options Language Extensions Compiler-specific Features C and C++ Implementation Details What is Semihosting? Via File Syntax Summary Table of GNU Language Extensions Standard C Implementation Definition Standard C++ Implementation Definition C and C++ Compiler Implementation Limits

Pragmas recognized by the compiler

3.13 Pragmas recognized by the compiler

The compiler recognizes a number of pragmas, used to instruct the compiler to use particular features.

The compiler recognizes the following pragmas:

Pragmas for saving and restoring the pragma state

  • #pragma pop
  • #pragma push

Pragmas controlling optimization goals

  • #pragma Onum
  • #pragma Ospace
  • #pragma Otime

Pragmas controlling code generation

  • #pragma arm
  • #pragma thumb
  • #pragma exceptions_unwind, #pragma no_exceptions_unwind

Pragmas controlling loop unrolling

  • #pragma unroll [(n)]
  • #pragma unroll_completely

Pragmas controlling Precompiled Header (PCH) processing

  • #pragma hdrstop
  • #pragma no_pch

Pragmas controlling anonymous structures and unions

  • #pragma anon_unions, #pragma no_anon_unions

Pragmas controlling diagnostic messages

  • #pragma diag_default tag[,tag,...]
  • #pragma diag_error tag[,tag,...]
  • #pragma diag_remark tag[,tag,...]
  • #pragma diag_suppress tag[,tag,...]
  • #pragma diag_warning tag[, tag, ...]

Miscellaneous pragmas

  • #pragma arm section [section_type_list]
  • #pragma import(__use_full_stdio)
  • #pragma inline, #pragma no_inline
  • #pragma once
  • #pragma pack(n)
  • #pragma softfp_linkage, #pragma no_softfp_linkage
  • #pragma import symbol_name
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