diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/doc/extend.texi | 23 |
2 files changed, 18 insertions, 10 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 70bf17e..a57eed5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2014-06-29 David Wohlferd <dw@LimeGreenSocks.com> + + * doc/extend.texi (Function Attributes): Update 'naked' attribute + documentation. + 2014-06-29 Tobias Grosser <tobias@grosser.es> PR bootstrap/61650 diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index ed9d141..cdfcce7 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -3358,16 +3358,15 @@ allowed value is 1000000. @item naked @cindex function without a prologue/epilogue code -Use this attribute on the ARM, AVR, MCORE, MSP430, NDS32, RL78, RX and SPU -ports to indicate that the specified function does not need prologue/epilogue -sequences generated by the compiler. -It is up to the programmer to provide these sequences. The -only statements that can be safely included in naked functions are -@code{asm} statements that do not have operands. All other statements, -including declarations of local variables, @code{if} statements, and so -forth, should be avoided. Naked functions should be used to implement the -body of an assembly function, while allowing the compiler to construct -the requisite function declaration for the assembler. +This attribute is available on the ARM, AVR, MCORE, MSP430, NDS32, +RL78, RX and SPU ports. It allows the compiler to construct the +requisite function declaration, while allowing the body of the +function to be assembly code. The specified function will not have +prologue/epilogue sequences generated by the compiler. Only Basic +@code{asm} statements can safely be included in naked functions +(@pxref{Basic Asm}). While using Extended @code{asm} or a mixture of +Basic @code{asm} and ``C'' code may appear to work, they cannot be +depended upon to work reliably and are not supported. @item near @cindex functions that do not handle memory bank switching on 68HC11/68HC12 @@ -6304,6 +6303,8 @@ Using Extended @code{asm} will typically produce smaller, safer, and more efficient code, and in most cases it is a better solution. When writing inline assembly language outside of C functions, however, you must use Basic @code{asm}. Extended @code{asm} statements have to be inside a C function. +Functions declared with the @code{naked} attribute also require Basic +@code{asm} (@pxref{Function Attributes}). Under certain circumstances, GCC may duplicate (or remove duplicates of) your assembly code when optimizing. This can lead to unexpected duplicate @@ -6423,6 +6424,8 @@ programs. Note that Extended @code{asm} statements must be inside a function. Only Basic @code{asm} may be outside functions (@pxref{Basic Asm}). +Functions declared with the @code{naked} attribute also require Basic +@code{asm} (@pxref{Function Attributes}). While the uses of @code{asm} are many and varied, it may help to think of an @code{asm} statement as a series of low-level instructions that convert input |