Fix incorrect character case of the CMAKE_INTERPROCEDURAL_OPTIMIZATION_* names

[phprus]

The names CMAKE_INTERPROCEDURAL_OPTIMIZATION_* must be uppercase.
Variable names in CMake are case-sensitive.

Bug in PR #1233.

LTO will not be disabled in zlib-ng only if in the parent project any of the CMAKE_INTERPROCEDURAL_OPTIMIZATION_{RELEASE,RELWITHDEBINFO, * } variables are defined to ON.

If the parent project defined only CMAKE_INTERPROCEDURAL_OPTIMIZATION everything works fine.

[codecov]

Codecov Report

Merging #1267 (ea2fdc1) into develop (f8a7f26) will increase coverage by 0.04%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop    #1267      +/-   ##
===========================================
+ Coverage    87.29%   87.34%   +0.04%     
===========================================
  Files          115      115              
  Lines        10202    10202              
  Branches      2574     2574              
===========================================
+ Hits          8906     8911       +5     
+ Misses         967      963       -4     
+ Partials       329      328       -1     

Flag	Coverage Δ
macos_clang	33.33% <ø> (ø)
macos_gcc	74.95% <ø> (ø)
ubuntu_clang	87.42% <ø> (ø)
ubuntu_clang_debug	86.96% <ø> (ø)
ubuntu_clang_inflate_allow_invalid_dist	87.12% <ø> (ø)
ubuntu_clang_inflate_strict	87.37% <ø> (ø)
ubuntu_clang_mmap	86.70% <ø> (-0.86%)	⬇️
ubuntu_clang_pigz	40.95% <ø> (ø)
ubuntu_clang_pigz_no_optim	41.14% <ø> (ø)
ubuntu_clang_pigz_no_threads	40.53% <ø> (ø)
ubuntu_clang_reduced_mem	87.82% <ø> (ø)
ubuntu_gcc	77.01% <ø> (ø)
ubuntu_gcc_aarch64	77.31% <ø> (ø)
ubuntu_gcc_aarch64_compat_no_opt	75.36% <ø> (ø)
ubuntu_gcc_aarch64_no_acle	76.20% <ø> (ø)
ubuntu_gcc_aarch64_no_neon	76.09% <ø> (ø)
ubuntu_gcc_armhf	77.32% <ø> (ø)
ubuntu_gcc_armhf_compat_no_opt	75.28% <ø> (ø)
ubuntu_gcc_armhf_no_acle	77.34% <ø> (ø)
ubuntu_gcc_armhf_no_neon	77.10% <ø> (ø)
ubuntu_gcc_armsf	77.19% <ø> (ø)
ubuntu_gcc_armsf_compat_no_opt	74.95% <ø> (ø)
ubuntu_gcc_benchmark	75.00% <ø> (ø)
ubuntu_gcc_compat_no_opt	76.50% <ø> (ø)
ubuntu_gcc_compat_sprefix	75.10% <ø> (ø)
ubuntu_gcc_m32	74.84% <ø> (ø)
ubuntu_gcc_mingw_i686	0.00% <ø> (ø)
ubuntu_gcc_mingw_x86_64	0.00% <ø> (ø)
ubuntu_gcc_no_avx2	76.66% <ø> (+0.80%)	⬆️
ubuntu_gcc_no_ctz	74.76% <ø> (ø)
ubuntu_gcc_no_ctzll	74.80% <ø> (ø)
ubuntu_gcc_no_pclmulqdq	75.44% <ø> (ø)
ubuntu_gcc_no_sse2	76.72% <ø> (ø)
ubuntu_gcc_no_sse4	76.26% <ø> (ø)
ubuntu_gcc_o1	75.97% <ø> (ø)
ubuntu_gcc_osb	∅ <ø> (∅)
ubuntu_gcc_pigz	38.90% <ø> (+0.05%)	⬆️
ubuntu_gcc_pigz_aarch64	39.29% <ø> (-0.09%)	⬇️
ubuntu_gcc_ppc	73.82% <ø> (ø)
ubuntu_gcc_ppc64	74.56% <ø> (ø)
ubuntu_gcc_ppc64le	74.54% <ø> (ø)
ubuntu_gcc_ppc_no_power8	74.74% <ø> (ø)
ubuntu_gcc_s390x	74.73% <ø> (ø)
ubuntu_gcc_s390x_dfltcc	72.09% <ø> (ø)
ubuntu_gcc_s390x_dfltcc_compat	73.63% <ø> (ø)
ubuntu_gcc_s390x_no_crc32	74.51% <ø> (ø)
ubuntu_gcc_sparc64	74.62% <ø> (ø)
ubuntu_gcc_sprefix	74.89% <ø> (ø)
win64_gcc	73.96% <ø> (ø)
win64_gcc_compat_no_opt	73.98% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
gzlib.c	71.10% <0.00%> (ø)
arch/x86/adler32_avx512.c	100.00% <0.00%> (+12.19%)	⬆️

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[Dead2]

I don't fully understand why this fix is needed, but it looks good to me.

[phprus]

@Dead2

For example, parent project:

# Enable LTO only for Release build.
set(CMAKE_INTERPROCEDURAL_OPTIMIZATION_RELEASE ON)

add_subdirectory(zlib-ng)

In zlib-ng, the CMAKE_INTERPROCEDURAL_OPTIMIZATION_RELEASE variable will not be overwritten (PR #1233) and CMake controlled LTO will not be disabled.

When developing PR #1233, I missed the point that the variable names in CMake are case-sensitive, and in the CMAKE_CONFIGURATION_TYPES list, configuration names are not in upper case :(

[Dead2]

@phprus Ah, now it makes sense, thanks for explaining it. 👍