From aad8d06c3f0f3a248c983c6186db7f8d439059c1 Mon Sep 17 00:00:00 2001 From: Tido Klaassen Date: Tue, 6 Oct 2015 08:04:14 +0200 Subject: make: rename CFLAGS in target Makefiles to TGT_CFLAGS Renamed every instance of variable CFLAGS in target specific Makefiles to TGT_CFLAGS to free up CFLAGS for user defined compiler flags. Added information in README.md about existence and usage of CFLAGS environment variable in build process. --- README.md | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'README.md') diff --git a/README.md b/README.md index 8b0987f3..2a262294 100644 --- a/README.md +++ b/README.md @@ -90,6 +90,7 @@ them as environment variables, for example: $ VARIABLE=value make * `FP_FLAGS` - Control the floating-point ABI + If the Cortex-M core supports a hard float ABI, it will be compiled with floating-point support by default. In cases where this is not desired, the behavior can be specified by setting `FP_FLAGS` Currently, M4F cores default @@ -100,6 +101,17 @@ them as environment variables, for example: $ FP_FLAGS="-mfloat-abi=soft" make # No hardfloat $ FP_FLAGS="-mfloat-abi=hard -mfpu=magic" make # New FPU we don't know of +* `CFLAGS` - Add to or supersede compiler flags + + If the library needs to be compiled with additional flags, they can be + passed to the build system via the environment variable `CFLAGS`. The + contents of `CFLAGS` will be placed after all flags defined by the build + system, giving the user a way to override any default if necessary. + + Examples: + + $ CFLAGS="-fshort-wchar" make # compile lib with 2 byte wide wchar_t + Example projects ---------------- -- cgit v1.2.3